[README.md] add Travis and Appveyor badges

Author: chrissimpkins

README.md

@@ -1 +1,5 @@
 ## fdiff
+
+[![Build Status](https://travis-ci.org/source-foundry/fdiff.svg?branch=master)](https://travis-ci.org/source-foundry/fdiff)
+[![Build status](https://ci.appveyor.com/api/projects/status/eafvbkc4iyv78dip/branch/master?svg=true)](https://ci.appveyor.com/project/chrissimpkins/fdiff/branch/master)
+