Removed TileEventType.TICK, use ITickable when really needed.
The few tiles needing to tick and are not a grid tile now implement ITickable.
Charger is no longer implementing ITickable.
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.