Modules: Allow disabeling built in modules

[Jowan-Spooner]

While you can already hide events from the event list I think in many cases people could disable whole modules that they don't need. This would be useful for builtin modules as we don't want people going in the addons folder and modifying stuff there, as that stuff breaks with any update.

If this would be enabled on the indexer-level it would mean we could pretty easily disable EVERYTHING from the module. Most likely it would be an editor setting that stores a list of disabled module names that is checked when the indexers are listed first.

Disabeling a module would remove it's whole apprearance: editors, subsystems, events, etc. This is super useful in removing clutter from the editor for an even better working experience.

We should probably also allow marking modules as essential and non-disableable because some things might break without certain events (aka text and end branch as the most important ones).