Re add plugin
Adjustments to current wrapper headerfiles.
Works as world plugin.
ROS formatting
Plugin ROS formatting.
Use WorldPose because BoundingBox may be missing/wrong.
Reduce code duplication.
Comments.
Cleanup.
Merge branch 'plugin'

Conflicts:
	include/TestWrapper.hh
	include/gztest/test_helpers.h
	src/TestWrapper.cpp