Added link to src code documentation in README.md

- Added link to read the docs.
- Added badges for Travis build and RTD status.

README.md

@@ -1,3 +1,6 @@
+[![Build Status](https://travis-ci.org/NOAA-GFDL/MOM6.svg?branch=dev/master)](https://travis-ci.org/NOAA-GFDL/MOM6)
+[![Read The Docs Status](https://readthedocs.org/projects/mom6/badge/?badge=latest)](http://mom6.readthedocs.io/)
+
 # MOM6
 
 This is the MOM6 source code.
@@ -6,6 +9,8 @@ This is the MOM6 source code.
 
 Start at the [MOM6-examples wiki](https://github.com/NOAA-GFDL/MOM6-examples/wiki) which has installation instructions.
 
+[Source code documentation](http://mom6.readthedocs.io/) is hosted on read the docs.
+
 # What files are what
 
 The top level directory structure groups source code and input files as follow: