velocityHelpers is exported with a lowercase starting letter.

[myanime]

in index.js you export the module 'velocityHelpers', but then in your examples you write:
var Animations = { down: VelocityHelpers.registerEffect({...

seems to make more sense to export the module with a Capital Letter? Or if this would break the plugin I guess at least fix up the examples. I can do a PR if you like, to fix the examples.