Enhancement: Improve Button Type Handling

[StormFX]

• [x] Improve the type-checking function to allow for additional types and due to Classic using CheckButtons for its bag bar.
• [x] Add additional sub-types for Item buttons.
• [x] Allow skins to use root or sub-types. Eg, Aura or Buff, etc.

Note: This will allow skins to use the root type as a fall-back for sub-types if the settings are the same.