Make chips drag-and-droppable

[isaaclyman]

Describe your idea

It would be cool if Cashmere chips had some off-the-shelf drag-and-drop features. CDK has a module for this: https://material.angular.io/cdk/drag-drop/overview

This feature should definitely be optional, but there are situations where order matters and it's useful to rearrange chips.

Whenever the chips are rearranged, an event should be fired.

[andrew-frueh]

@WistyDagel @MarielaCisneros - gonna queue this one up for you both because it's very similar to what you're doing for #647