Filled out the readme

README.rst

@@ -3,3 +3,34 @@ PyNaCl
 
 .. image:: https://travis-ci.org/dstufft/pynacl.png?branch=master
     :target: https://travis-ci.org/dstufft/pynacl
+
+PyNaCl is a Python binding to the `Networking and Cryptography library`_,
+a crypto library with the stated goal of improving usability, security and
+speed.
+
+.. _Networking and Cryptography library: http://nacl.cr.yp.to/
+
+
+Installation
+------------
+
+PyNaCl relies on libsodium_, a portable C library which can be compiled
+on a variety of systems. It may already be available from your package
+manager.
+
+.. _libsodium: https://github.com/jedisct1/libsodium
+
+Once libsodium is installed, PyNaCl can be installed by:
+
+.. code-block:: bash
+
+    $ python setup.py install
+
+
+Features
+--------
+
+* Digital signatures
+* Secret-key encryption
+* Public-key encryption (coming soon)
+* HMAC (coming soon)