rqt_marble) Adjust to removal of rqt_cpp_common.
rqt_cpp_common removed (suggested in https://github.com/ros-visualization/rqt_common_plugins/issues/191)
rqt_marble) Correct plugin description on left-top of the top widget.
rqt_marble) Correct CMakeLists.txt (in reponsese to the comment https://github.com/130s/rqt_common_plugins/commit/c2936e0b93f9a811c378342c63a753c7c95239f5#commitcomment-4337334)
Merge pull request #192 from 130s/rm_cpp_common

Remove rqt_cpp_common