Add some basic files for a dependency graph

DepsToDot.hs from
https://github.com/EvgenyMakarov/math-classes/blob/master/tools/DepsToDot.hs
Update various scripts for dependency graph
Use a separate travis instance for the dep graph

Also actually build quick doc
Be slightly nicer about when to build things
Only install python stuff for proviola
Be more verbose about commands run on travis
Merge pull request #320 from JasonGross/deps-to-dot

Have Travis build us a dependency graph
Don't build the dependency graph when making html

Also, git remote update before checking out, so that we race less