Minor tweaks and fixes for airlock equipment

- Fixed DP vent pumps not changing direction
- Made airlock_sensor more versatile (and backwards compatible with old airlock code)
- Added airlock_sensor and access_button airlock subtypes for easier mapping
Airlock controller rewrite

- /datum/computer/file/embedded_program moved from embedded_controller_base.dm to code/game/machinery/embedded_controller/airlock_program.dm
- embedded_controller_base.dm cleaned up and identical parts of the controller subtypes were moved here
- embedded_controller subtypes moved to code/game/machinery/embedded_controller/airlock_controllers.dm
- Added nanoUI templates for airlock controllers
- Added a couple of classes to nano/css/shared.css for colouring buttons
- Minor map update to maintain airlock compatibility and fix a broken airlock near virology
Airlock update

- Should now merge
Merge pull request #4408 from Loganbacca/airlock-merge

Airlock controller rewrite