Support new set of worm features in OWAT

[cheelee]

Avelino's made some new (better) features that we're just about to publish as part of the OpenWorm Philosophical Transactions special issue. I think it would be good to get those into OWAT and possibly deprecate the 2013 features. The new ones are already written in Python so it might be a bit less work than porting Ev's original Matlab code.