New suit sensor toggle menu

This is mostly ported from bay and NT. Credit where it's due. Instead of cycling through your suit sensor modes, which is horrible since they're randomized on spawn and takes a long time, there's a menu you can select different modes from.

New proc for setting suit sensor mode included.

![ss 2014-08-12 at 05 54 51](https://cloud.githubusercontent.com/assets/7247232/3900028/76a239f8-2284-11e4-9094-93087b129722.png)

The setting currently being used by your jumpsuit will be highlighted blue when you open the menu.
Rename the usr to user to avoid possible issues with BYOND mistaking it for the built-in variable which is not reliable.