added webpage URLs in description

Author: Andrea Censi

README.md

@@ -4,4 +4,5 @@ Note: there are two branches on the repository. The "master" branch uses GSL.
 
 This is the ``csm_eigen`` branch, which uses the ``eigen`` library. 
 This branch is the work of people working at U. Freiburg and Kuka, 
-including Christoph Sprunk and Rainer Kuemmerle.
+including [Christoph Sprunk](http://www.informatik.uni-freiburg.de/~sprunkc/) 
+and [Rainer Kuemmerle](http://www.informatik.uni-freiburg.de/~kuemmerl/).