Orgl&Bert level BackFollow is WORKING!!!!

[Mark S. Miller <mark>]

This backFollow is:
	1) transitive across a multiOrgl in both directions
	2) actually works by navigating backwards (via Necromancers)
	3) looks like it works correctly.

Link level BackFollow isn't working yet.  However, the really
important consideration is that I should be able to get it working
without having to do any massive recompiles ;-\