Make CONTRIBUTING a proper markdown file.

Author: gconnell

CONTRIBUTING CONTRIBUTING.md

@@ -1,6 +1,9 @@
+Contributing To Stenographer
+============================
+
 Want to contribute? Great! First, read this page (including the small print at the end).
 
-### Before you contribute
+### Before you contribute ###
 Before we can use your code, you must sign the
 [Google Individual Contributor License Agreement](https://developers.google.com/open-source/cla/individual?csw=1)
 (CLA), which you can do online. The CLA is necessary mainly because you own the
@@ -15,10 +18,10 @@ us first through the issue tracker with your idea so that we can help out and
 possibly guide you. Coordinating up front makes it much easier to avoid
 frustration later on.
 
-### Code reviews
+### Code reviews ###
 All submissions, including submissions by project members, require review. We
 use Github pull requests for this purpose.
 
-### The small print
+### The small print ###
 Contributions made by corporations are covered by a different agreement than
 the one above, the Software Grant and Corporate Contributor License Agreement.