Updated CMakeLists.txt to link to the indigo version.
Update CMakeLists.txt to Link to Indigo

This is a very simple change that fixes the CMakeLists.txt file link to
point to the indigo version of ROS, instead of hydro.  The main goal of
this pull request is to test the process for future changes.

Merge with "islamelnabarawy:master"

Author: Islam Elnabarawy <ie3md@mst.edu>