Add doc

README.md

@@ -2,24 +2,34 @@
 
 ---- 
 
-Code
-----
+# Code
+
 https://gitlab.in2p3.fr/CTA-LAPP/PHOENIX_LIBS/PhoenixHPCProxy
 
-Documentation
-----
+# Documentation
+
 https://cta-lapp.pages.in2p3.fr//PHOENIX_LIBS/PhoenixHPCProxy/
 
-Requirements
-------------
+# Requirements
+
 
 - c++ compiler >=5.3.1 
 - cmake > 3
 - make
 
-Installation for Users
-----------------------
+# Installation for Users
+
 	$ git clone https://gitlab.in2p3.fr/CTA-LAPP/PHOENIX_LIBS/PhoenixHPCProxy.git
 	$ cd PhoenixHPCProxy
 	$ ./install.sh
 
+# Quick Start
+
+The program **phoenix_hpc_proxy** can generates automatically a proxy library to dynamically choose between several architecture to target.
+
+![proxy principle](doc/proxy_principle.png)
+
+
+
+
+