updated bank functions.

Added OpenBankNPCEx(color:string) which accepts 3 banker colours (grey, blue, green) And updated the old blue colour since it was heavily outdated.
Changed OpenBankNPC to just use OpenBankNPCEx (uses the blue banker), mainly there to prevent breaking scripts.
Updated OpenDepositBox to actually work at the correct boxes + uses a more advanced method then findobjtpa.
Merge pull request #148 from Ollybest/patch-2

updated bank functions.