Quick add/remove parens around function args.

![coffee](https://cloud.githubusercontent.com/assets/3876443/3819389/3bfbfed2-1cea-11e4-94c6-e3f2e6f39a69.gif)

Added to Command List, and as keybinds.

Overrides default sublime paren-wrapping behavior when the selection starts immediately after a space. Open to debate re: the keys used in keybindings.