Update README.md

Author: sbromberger

README.md

@@ -1,5 +1,8 @@
 # CommunityDetection
 
 [![Build Status](https://travis-ci.org/sbromberger/CommunityDetection.jl.svg?branch=master)](https://travis-ci.org/sbromberger/CommunityDetection.jl)
-
 [![codecov.io](http://codecov.io/github/sbromberger/CommunityDetection.jl/coverage.svg?branch=master)](http://codecov.io/github/sbromberger/CommunityDetection.jl?branch=master)
+
+### CommunityDetection.jl 
+
+Implements community detection for LightGraphs. Both Nonbacktracking and Bethe Hessian detection are supported.