Merge pull request #44 from JimHokanson/master

updates to path features
Stabilized the code so it will run

Basically just added a path attribute to WormPath because WormFeatures
was looking for it.
Added an installation guide
Fixed comments and added slightly to locomotion
cleaned up documentation, worked on locomotion
add interpolation command in locomotion
Merge pull request #9 from openworm/master

From M to J