Replaces the reflexive instantiation of the Renderes with a factory
method.
Some optimizations to the renderers to no longer push the whole OpenGL state to the stack.
General cleanup of duplicate code, etc
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.
Every Block had a call to its super, passing its own class.
This can easily be simulated by calling `this.getClass()` in the super class.
Also this was basically only used as using a name.
In the future it might be advisable to not use such methods,
since they are prone to refactoring.
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.
To integrate these into the current system, some changes to the background had to be done, especially to the feature handler. It now uses an interface to work against which you can implement to get your own feature handler instead modifying the base one and add several special cases code
