Additional features for Mod/Settings API

[Elliesaur]

These are all just some observations I have on the mod/settings API currently. These listed items I can work on if you'd like.

Mod/Settings API should be enhanced to add the following items:

• Supporting buttons in settings window with custom callback
• Adding additional metadata fields such as mod name, version, author
• Example mod that details the process/how to make (maybe docs for it) a mod
• (mentioned in Mediapipe Video Device Dropdown box  #83) Support an easy way to save/load a particular selected item in a menu list
• Properly support selected item in the menu list - the current "hack" is using an "array" as the property data type and getting the first item (only item)
• Expose and document more methods in the mod api/other areas - getting camera and so on should be in the mod api like getting a skeleton is?

Anyway, food for thought! Good to start these discussions about what might be the limitation of the mod/settings API.