Merge pull request #18 from DaveAckley/master

Cleaning, generalizing, abstracting
Post paper hackage. Ready for nasty merge.
Merge conflicts of post-paper pull request
Added nuking functionality, currently triggered by SDLK_n
Implemented XRay
Renaming of files to reflect contents
Added buttons to stats renderer. See mfmsim driver for details.
Give us this day our daily merge, part one
Add PSym, support for point symmetries on coords.  (Our daily merge, part two)
Fix Grid::PlaceAtom, I believe.  (Our daily merge, part three)
Work in mfmdha on qbar and qbar-related technologies.  (Our daily merge, part the last)