[CS] Code Style fixes. Closes #4277, closes #4304, closes #4305
[CS] CodeStyle on joomla.sql. Closes #4298
Added events map property.

This allows for events to be mapped to plugin groups independently.
Synced with latest JModelAdmin changes.
Trigger extension save events on config save actions.
Trigger content save and delete events.
Consistency fix.
Load user plugins.

Plugins are not loaded before the onUserAuthorisationFailure is triggered.