cleanup a bunch of files

these changes were made after looking at landscape.io
a bit more style cleanup
a bit more clean up

also, remove our implementation of BFGS because it was crap and unused.
Merge remote-tracking branch 'origin/pr/73' into cleanup_style

to avoid conflicts
more style upates
Merge branch 'master' of github.com:pele-python/pele into cleanup_style
make the spin models more robust
a bit of cleanup in the gui code
more style fixes
Merge pull request #74 from js850/cleanup_style

cleanup a bunch of files