Money/Vending machine PR

Full list of changes!

1) Money! The new system has a chance for charged cash cards to spawn after killing zombies. These carry money (measured in cents) and can be used to buy things at vending machines.
2) Vending machines! They work and will dispense things after you put a charged cash card in them. These can be bashed, but are alarmed similar to some windows/doors.
3) ATMs. These spawn in banks and can be used to transfer money to and from your bank account and cash cards, as well as from one cash card to another. They can also print new cash cards for a small fee from your account.
4) New bank layout.
5) Converted all json prices. Needless to say some of these are really weird now, but I just did a basic blanket conversion. Actual realistic pricing will need to be added later.
6) __Added the ability to have items spawn with varying amount of charges.__ This can be seen on the cash card and currently works on tools and comestibles. This can be explicitly overridden to spawn items with their set charges (used for vending machines currently to insure full drinks/food inside them).
7) Added the ability to create vending machines that use any spawnlist in the json mapgen files. Just add a "type":"*insert spawnlist name here*" field in the special placement for the vending machine and it will draw on whatever spawnlist you add.

Behind the scenes stuff:
1) Charges are now stored as longs, in case you ever needed that many (currently the only feasible use is if a player starts storing all of their money on a single cash card).
2) Added a few new json functions to handle said long values as opposed to normal integers.

Other stuff:
Small office mapgen safe tile fix.