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.
Deprecates the old usage of the AEItemDefinitions via the direct method access of
* blocks()
* parts()
* items()
* materials()
and thus use the new re-direct via definitions().
All definitions are now initialized, no matter what. But SubItems, Items and Blocks are not registered, if by chance are disabled.
