cleans up reagent_dispenser.dm

water coolers now dispense paper cups into empty hands.
adds a cup limit to the water cooler.

Fixed a potential bug I may of caused involving reagent dispensor ex_act and blob_act.
Merge branch 'master' of https://github.com/tgstation/-tg-station into papercups
Fixes an accidental oversight in replenishing cups. It now turns paper into cups using magic.
Merge pull request #2310 from KazeEspada/papercupsshallconsumetheworldwiththeirtrash

paper cups