Merge pull request #27 from JenniferBuehler/melodic_support

gazebo_grasp_plugin/CMakeLists.txt

...grasp_plugin/include/gazebo_grasp_plugin/GazeboGraspFix.h

gazebo_grasp_plugin/package.xml

gazebo_grasp_plugin/src/GazeboGraspFix.cpp

gazebo_grasp_plugin/src/GazeboGraspGripper.cpp

gazebo_state_plugins/CMakeLists.txt

gazebo_state_plugins/package.xml

gazebo_state_plugins/src/GazeboMapPublisher.cpp

gazebo_state_plugins/src/GazeboObjectInfo.cpp

gazebo_version_helpers/CMakeLists.txt

...ers/include/gazebo_version_helpers/GazeboVersionHelpers.h

gazebo_version_helpers/package.xml

gazebo_version_helpers/src/GazeboVersionHelpers.cpp