* Move the UI code out of the plugin logic.
* Add types where needed.
* Move into game package.
* Improve error handling.
* Simplify settings behavior.
* Don't load disabled plugins.
* Remove knowledge of non-base plugins from game generation.
Fixes https://github.com/Khopa/dcs_liberation/issues/311
The changes for Skynet unfortunately broke this because the names used
by the TGO and the name of the group itself were no longer in sync.
This deserves a larger cleanup where we decouple that naming
requirement (TGOs don't need a lot of the data they currently have),
but this works until we have the time to do that.
Fixes https://github.com/Khopa/dcs_liberation/issues/298
