Merge pull request #42 from jhprinz/master

Moved storage related files into a packege named storage
Calculations, with Bootstrap starting us off.
Merge pull request #43 from jhprinz/master

improves storageview and adds showtree
Merge remote-tracking branch 'upstream/master' into calculation
Added convenience methods; bootstrapping example.

Convenience methods for volume set, ensemble set, and OneWayShooterSet.
Bootstrapping seems to be working in the ala_dipeptide example, too.
Merge pull request #45 from dwhswenson/calculation

Calculations & Factories
little changes to showtree. Looks better now and has an option to show/hide rejected paths
Merge branch 'master' of github.com:choderalab/msm-tis
updated showtree.py to look nicer