Refactored AEConfig (#2633)

Added a singleton getter instead the public field.
Reduced all fields to private.
Replaced field access with getters.
Added setters where necessary (Dimension/Biome Registration)
Added config options to disable more features.
Splitted Enum name from the config key.
Changed FacadeConfig and Networkhandler similar to AEConfig.init().

src/main/java/appeng/block/misc/BlockQuartzFixture.java

@@ -135,7 +135,7 @@ public class BlockQuartzFixture extends AEBaseBlock implements IOrientableBlock,
 	@SideOnly( Side.CLIENT )
 	public void randomDisplayTick( final IBlockState state, final World w, final BlockPos pos, final Random r )
 	{
-		if( !AEConfig.instance.enableEffects )
+		if( !AEConfig.instance().isEnableEffects() )
 		{
 			return;
 		}