Added atmos and jani watertanks, changed nozzle types [MAP]

* Changes hydroponics watertank backpack nozzle type to act more like a spray/mister
* Changes sprays to be used on hydro trays correctly (Interaction code for reagent_containers needs a hell of a redo)
* Added a janitorial watertank to the closet, identical to the hydro one except for colour scheme
* Added an atmos watertank with a fire extinguisher nozzle

You probably shouldn't let the clown get his hands on these.

Used recolours of validsalid's original sprite, done by Nienhaus:

![](http://puu.sh/7lmWq.dmi)