Update documentation

README.md

 # Installation
 
-## Requirements
+### Using VENV :
 
-First clone this repo somewhere on your computer.
-Lets say `~/Documents/inria/yggdrasil` for instance.
+In project root directory :
+```
+virtualenv venv
+source venv/bin/activate
+```
 
-To make things easier for you, you can update your bashrc (or whatever
-equivalent) with those lines :
+### installing the lib in dev mode :
 
+In project root directory
 ```
-export PATH=$PATH:$GOPATH/bin:~/Documents/inria/yggdrasil/python:~/Documents/inria/yggdrasil/python/isengard:~/Documents/inria/yggdrasil/python/erebor:~/Documents/inria/yggdrasil/python/task_lib
-export PYTHONPATH=$PYTHONPATH:~/Documents/inria/yggdrasil/python:~/Documents/inria/yggdrasil/python/isengard:~/Documents/inria/yggdrasil/python/erebor:~/Documents/inria/yggdrasil/python/task_lib
+pip install -e .
 ```
 
-If you dont, it's okay, there is a special launcher able to execute the program
-without the path setup.
+# Requirements
 
 ### Needed softwares/libraries :
 
@@ -23,7 +24,9 @@ without the path setup.
 * pyzmq `sudo aptitude install python3-zmq`
 * pexpect `sudo aptitude install python3-pexpect`
 
-### SSH config file containing
+# Local configuration for dev purposes
+
+## SSH config file containing :
 
 ```
 Host A
@@ -48,7 +51,7 @@ Host F
 
 Replacing $USERNAME$ by your user name.
 
-### /etc/hosts containing
+## /etc/hosts containing :
 
 ```
 127.0.1.1	A
@@ -66,13 +69,15 @@ Replacing $USERNAME$ by your user name.
 127.0.1.1	M
 ```
 
-### SSHD config
+## SSH Config
 
-Ensure no max session is set.
+### ~/.ssh/config: (locally)
+
+SendEnv PATH
+SendEnv PYTHONPATH
 
-## Testing installation
+### /etc/ssh/sshd_config: (on the remote end)
 
-If everything is done properly, you should be able to run the `./regression.sh`
-script in the python folder. If not, and if you are sure of your configuration,
-try to run each example one after the other to see what is wrong and consider
-adding an issue in the bug tracker.
+AcceptEnv PATH
+AcceptEnv PYTHONPATH
+Ensure no max session is set.