make rostest in CMakeLists optional (ros/rosdistro#3010)
Merge pull request #175 from bulwahn/indigo-devel

make rostest in CMakeLists optional (ros/rosdistro#3010)
Export missing libraries.
Fix PLUGINLIB_DECLARE_CLASS depreacation warnings.
Merge pull request #178 from pal-robotics/tr-iface-cmake

Misc transmission_interface build fixes.