Introduces new ToggleSwitch

Replaces `Bluemoon` with a new `Abstract` based ToggleSwitch.

Basically I just cloned [Digit's ToggleSwitch](https://github.com/montagejs/digit/tree/master/ui/toggle-switch.reel) and adjusted the styling to fit the rest of Matte.

![toggle-switch](https://f.cloud.github.com/assets/378023/1437165/c5b9d30a-4168-11e3-8871-0b965d0d92d1.gif)