RFC:  roll forward master into machinekit

this one warrants discussion and a test. I have stopped merging forward changes to debian/* ; folks working on packaging might have a look themselves

+ adds assorted fixes from g.l.o master
+ updated hm2 support
+ runtests ok
- it could be this broke parallel builds again - I' appreciate a second pair of eyes (how do I funnel this through the buildbot these days?)

in general, not sure how we should handle dealing with g.l.o downstream - wholesale merges might be problematic, just cherry-picking is more work. Suggestions welcome.