Fixed forcefield generation of small molecule; use new function in gaff2xml that handles the gaff_dat file
Added the test that I'm currently using to see if systembuilder works. Should be clearned up a bit but still trying to resolve yank error
Added alchemy tests. will attempt to run
Merge pull request #54 from pgrinaway/new-driver

[WIP] Rewrite driver code, move to driver.py, introduce system builder classes
Merge remote-tracking branch 'choderalab/master' into new-driver

Conflicts:
	yank/systembuilder.py
Removed messy and unworkable example directory.