Fixing fuel/waste registries

Adding IReactorFuel interface and fixing registry.
Changing RendererControlRod and TileEntityReactorControlRod to use the
BR Registry for fuel validation now.
Removing IReactorFuelLiquid in favor of IReactorFuel.
Fixing multiblock reactors - control rods integrated

New Control Rod TEs integrated into reactors
Fixed config option to include other mods' uraniums as yellorium
Making FuelRods an IMultiblockPart so they can do their own assembly
validation
Lots of changes to TEControlRod to play nice with the MB update
framework
Removing some unused textures
Corifying some GUI update stuff into IBeefGuiEntity, shared between
TileEntityBeefBase and TileEntityReactorControlRod for gui updates.