refactor: improve basic ticketing support plugin snippet

[DevinWalker]

PR Description

Resolves #108 and #102

• Allows for multi-level form support
• Improves code so it's dryer and uses triggers from core
• Allows for various currency formatting
• Improves ticket input by having a max and min
• Allows to change gateways without losing total donation amount

A lot more can be done here but this is a decent improvement.