Improved town coffers system + plot taxing and selling

[Iotados]

Brief:

• [x] Withdrawl from Coffers; limited to amount to sustain current Chunks/Members.
• [ ] Setting Plot prices/Rent costs. Directly funds town coffers thus town level (configurable)
• [ ] Taxation on Towns server wide -- admin command.

Info extrapolated from Roadmap. See for further and expanded info.