Merge pull request #2240 from gabrieldemarmiesse/mention_contributing

Improved the readme.

README.rst

@@ -30,7 +30,7 @@ If you already have a C compiler, just do::
 otherwise, see `the installation page <http://docs.cython.org/en/latest/src/quickstart/install.html>`_.
 
 
-LICENSE:
+License:
 --------
 
 The original Pyrex program was licensed "free of restrictions" (see below).
@@ -39,6 +39,13 @@ Cython itself is licensed under the permissive **Apache License**.
 See `LICENSE.txt <https://github.com/cython/cython/blob/master/LICENSE.txt>`_.
 
 
+Contributing:
+-------------
+
+If you want to contribute to the Cython project, you should take a look
+at `those ressources <https://github.com/cython/cython/blob/master/docs/CONTRIBUTING.rst>`_.
+
+
 Get the full source history:
 ----------------------------