Schema rework | Update to roll command | DB functions updated

[sjkd23]

Roll command updates:

• Optional 'number' option for /roll, which allows you to roll for multiple Gachas at once.

  • When rolling multiple times, you can cycle through the Gachas you got using the 'Previous' and 'Next' buttons.
  • Only interaction user can use the buttons

• 'Roll Again!' button which prompts you to choose a number of rolls

  • User must send a message containing ONLY a number

• Each roll cost 10 coins/balance.

Database functions updated:

• Used findOrCreate in a lot of places, instead of making it two seperate 'find' and 'create' functions.
• Added documentation to new functions.
• Function names are (hopefully) intuitive.

New Database Schema:

• Added GACHA_URL_LIST array to the 'Gacha' database, instead of using the array itself in the code.