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.
Add Python helpers to make life easier.

- Helper for getting all active controller managers.

- Helper for determining if a namespace contains the controller manager ROS API.

- Helpers for filtering the output of the 'list_controllers' service by
  type, name, state, hardware_interface and claimed resources.