Update README.md - commands to install dependencies

Cmake have to be installed to avoid this error:

failed to run custom build command for `libz-sys v1.1.3`

README.md

@@ -31,6 +31,15 @@ See [duniter.org](https://duniter.org/) or for end user [monnaie-libre.fr](https
 
 #### In a post-it
 
+Install dependencies
+```
+curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
+curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.1/install.sh | bash
+nvm install 10.22.1
+sudo apt install cmake
+```
+
+Then build and start Duniter
 ```bash
 git clone https://git.duniter.org/nodes/typescript/duniter.git
 cd duniter