added group-info command
Added methods for manipulating branches (multiple connected sections)
Added hocRender command for MNTB project
Merge remote-tracking branch 'lcampagn/mntb' into headless

Conflicts:
	hocRender.py
	hoc_reader.py
Added missing hoc_viewer back to the repository
Changed hocRender to not show grid, and some pass-throughs to control cylinder appearance.
Changed hoc_graphics to handle the pass throughs from the render for cylinder appearance.