Variable gold pouch capacity

[Jerenaux]

The amount of gold that players can carry is unlimited at the moment. A new equipment type, the gold pouch, could be introduced, which would limit the amount of gold carried. Different pouches would allow to carry more or less gold.

In practice this would require:

• Introducing a new equipment slot for the gold pouch, which cannot be empty (a default basic pouch would be always equipped unless a better one is equipped)
• Putting and enforcing a cap on the gold amount based on the equipped pouch