* build rtabmap_viz with Qt5
* eliminate circular dependency (nothing can depend on rtabmap_ros that rtabmap_ros depends on), and resolve 'Unknown CMake command catkin_package' with catkin build
* more dependency cleanup but can't get rid of rtabmap_demos circular dependency on rtabmap_legacy
* Update CMakeLists.txt
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Co-authored-by: matlabbe <matlabbe@gmail.com>