gazebo_ros: also support gazebo instead of gazebo_ros as package name for plugin_path, gazebo_model_path or gazebo_media_path exports
gazebo_ros: added deprecated warning for packages that use gazebo as
package name for exported paths
Merge pull request #34 from meyerj/support_gazebo_package_name_for_plugins_patch

also support gazebo instead of gazebo_ros for package exports
Made version match the rest of gazebo_ros_pkgs per bloom
2.1.0
Adding contributing instructions
Merge pull request #55 from jhu-lcsr-forks/add-contributing

gazebo_ros_pkgs: Adding contributing instructions
Adding install targets
Update CONTRIBUTING.md
Update README.md
Update CONTRIBUTING.md
Merge pull request #56 from jhu-lcsr-forks/hydro-devel

Adding install targets
Added dependency to prevent missing msg header, cleaned up CMakeLists
Minor print modification
Removed searching for plugins under 'gazebo' pkg because of rospack warnings
Moved gazebo_interface.py from gazebo/ folder to gazebo_ros/ folder
Actually we need __init__.py
install diff_drive and skid_steer plugins
export diff drive and skid steer for other catkin packages
making RobotHWSim::initSim pure virtual