README: add contibution guidelines

No public repository makes sense unless we know how to contribute.

Signed-off-by: Nishanth Menon <nm@ti.com>

README

@@ -5,8 +5,15 @@ This is a motley collection of handy, dandy scripts and programs that
 are helpful when doing android development.  As we get more scripts in
 the future, we may add more organization.
 
+HOW TO CONTRIBUTE:
+-----------------
+Fork off the project and send a pull request on github to the project
+- Ensure that proper documentation is available incode
+- Ensure useful help messages are available for users to use it :)
+
 LICENSE RULES
 -------------
 
 All code here needs to be Apache 2 or public domain.  Please include
 license and copyright information at the top of each file.
+