Implement mod configurations, mod reordering, and extended exports

[Mr-Wiseguy]

This PR adds the following features:

• Mods can provide a config schema json that specifies fields that are user-configurable for the mod. This gets hooked up to a menu in the parent project to allow users to configure their mods.
• Mods can be reordered to change the order that their loading occurs. This also gets exposed in the menu by the parent project.
• Parent projects can now provide extended exports, which generate a shim between the function call and the base function that injects the caller mod's ID into the arguments. This provides a mechanism for exported functions to check what mod has called them.
• Exported functions have been created so that mods can read their config values.