Remove withinInteractionLimit check in pointerOver

No action to check with at that point.
Add Interaction#action

If resizing, interaction.prepared could be 'resizexy' but
interaction.action would be 'resize'. Not great but it's better than
always doing

var action = /resize/.test(this.prepared)? 'resize' : this.prepared;
Renane npm package to 'interact.js'

Re: #118