Merge pull request #7 from meyerj/hydro-devel

Use cmake macros instead of functions in GenerateRTTROSCommPackage.cmake.em
Adding some comments, removing old ROS_BUILD__TYPE setting
Merge branch 'hydro-devel' of github.com:jhu-lcsr-forks/rtt_ros_integration into hydro-devel
rtt_ros: removed dependency from non-existent package rtt_rostopic