diff --git a/Cargo.lock b/Cargo.lock
index 181bb51c9425f74b535112585af0287783c2c38d..5e3ac4d55b550aad46cb38cfcb455161c2cc08b4 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -630,6 +630,7 @@ dependencies = [
  "serde_json 1.0.38 (registry+https://github.com/rust-lang/crates.io-index)",
  "structopt 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "unwrap 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "uuid 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "ws 0.7.9 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
@@ -1084,6 +1085,33 @@ dependencies = [
  "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "rand"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.48 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_jitter 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_os 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_pcg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "rand_core"
 version = "0.3.1"
@@ -1097,6 +1125,62 @@ name = "rand_core"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "rand_hc"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_isaac"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_jitter"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.48 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_os"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "cloudabi 0.0.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fuchsia-cprng 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.48 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_pcg"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "autocfg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "rand_xorshift"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "rayon"
 version = "1.0.3"
@@ -1531,6 +1615,15 @@ dependencies = [
  "rand 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
+[[package]]
+name = "uuid"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.86 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
 [[package]]
 name = "vcpkg"
 version = "0.2.6"
@@ -1700,8 +1793,16 @@ dependencies = [
 "checksum rand 0.3.23 (registry+https://github.com/rust-lang/crates.io-index)" = "64ac302d8f83c0c1974bf758f6b041c6c8ada916fbb44a609158ca8b064cc76c"
 "checksum rand 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "552840b97013b1a26992c11eac34bdd778e464601a4c2054b5f0bff7c6761293"
 "checksum rand 0.5.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c618c47cd3ebd209790115ab837de41425723956ad3ce2e6a7f09890947cacb9"
+"checksum rand 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "6d71dacdc3c88c1fde3885a3be3fbab9f35724e6ce99467f7d9c5026132184ca"
+"checksum rand_chacha 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "556d3a1ca6600bfcbab7c7c91ccb085ac7fbbcd70e008a98742e7847f4f7bcef"
 "checksum rand_core 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6fdeb83b075e8266dcc8762c22776f6877a63111121f5f8c7411e5be7eed4b"
 "checksum rand_core 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d0e7a549d590831370895ab7ba4ea0c1b6b011d106b5ff2da6eee112615e6dc0"
+"checksum rand_hc 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "7b40677c7be09ae76218dc623efbf7b18e34bced3f38883af07bb75630a21bc4"
+"checksum rand_isaac 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "ded997c9d5f13925be2a6fd7e66bf1872597f759fd9dd93513dd7e92e5a5ee08"
+"checksum rand_jitter 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "1166d5c91dc97b88d1decc3285bb0a99ed84b05cfd0bc2341bdf2d43fc41e39b"
+"checksum rand_os 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "7b75f676a1e053fc562eafbb47838d67c84801e38fc1ba459e8f180deabd5071"
+"checksum rand_pcg 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "abf9b09b01790cfe0364f52bf32995ea3c39f4d2dd011eac241d2914146d0b44"
+"checksum rand_xorshift 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cbf7e9e623549b0e21f6e97cf8ecf247c1a8fd2e8a992ae265314300b2455d5c"
 "checksum rayon 1.0.3 (registry+https://github.com/rust-lang/crates.io-index)" = "373814f27745b2686b350dd261bfd24576a6fb0e2c5919b3a2b6005f820b0473"
 "checksum rayon-core 1.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "b055d1e92aba6877574d8fe604a63c8b5df60f60e5982bf7ccbb1338ea527356"
 "checksum rdrand 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "678054eb77286b51581ba43620cc911abf02758c91f93f479767aed0f90458b2"
@@ -1756,6 +1857,7 @@ dependencies = [
 "checksum url 1.7.2 (registry+https://github.com/rust-lang/crates.io-index)" = "dd4e7c0d531266369519a4aa4f399d748bd37043b00bde1e4ff1f60a120b355a"
 "checksum utf8-ranges 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "796f7e48bef87609f7ade7e06495a87d5cd06c7866e6a5cbfceffc558a243737"
 "checksum uuid 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)" = "e1436e58182935dcd9ce0add9ea0b558e8a87befe01c1a301e6020aeb0876363"
+"checksum uuid 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)" = "90dbc611eb48397705a6b0f6e917da23ae517e4d127123d2cf7674206627d32a"
 "checksum vcpkg 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "def296d3eb3b12371b2c7d0e83bfe1403e4db2d7a0bba324a12b21c4ee13143d"
 "checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"