Alikins/no rpm version

Probably some build/test issues to shake out, but it seems to work for me.

This generates version.py files that are populated with either the rpm version-release,
or 'git describe' like output (ie, more or less latest tag, how many commits since that
tag, and sha of HEAD). 

This removes a lot of runtime code, and removes code that was opening the
rpm database and querying it for two package names and versions. That was
taking on average about .5s every time the process started.