gazebo_plugins: terminate the service thread properly on destruction of a PubMutliQueue object without shuting down ros
Skid steering drive plugin.
Rotation fixed.
gazebo_ros_api_plugin.h is no longer exposed in the include folder
Merge pull request #41 from ZdenekM/hydro-devel

Added skid steering plugin (modified diff drive plugin).
Merge branch 'hydro-devel' of https://github.com/osrf/gazebo_ros_pkgs into terminate_service_thread_fix

Conflicts:
	gazebo_plugins/include/gazebo_plugins/PubQueue.h
Merge pull request #42 from osrf/api_plugin_no_include

gazebo_ros_api_plugin.h is no longer exposed in the include folder
Merge pull request #33 from meyerj/terminate_service_thread_fix

another fix for terminating the service_thread_ in PubQueue.h
Merge pull request #44 from osrf/robot_hw_sim

Renamed RobotSim to RobotHWSim
Merge remote-tracking branch 'origin/hydro-devel' into robot_hw_sim
Tweaked README