Reduces the visibility of all fields to private and create setters/getters
when necessary. Exceptions are fields with GuiSync as these need to be
public.
Reduces the visibility of internal methods to private/protected/default when possible.
Many exceptions got an improvement due to changed class or description or details it is providing.
Is not complete, needs to be done in patches in the regions, where it is needed, since some are just
swallowed.
Removed total usage of pure RuntimeExceptions to 0.
