Removes coremod (#3038)

From now on every integration must not rely on method stripping through
a coremod or @Optional. Notable example for a very good solution is IC2.

As consequence this drops all support for RF and mods must support on of
our supported energy types. At the time of writing, ForgeEnergy and
IC2/EU.

src/main/java/appeng/core/AppEng.java

@@ -33,7 +33,6 @@ import net.minecraft.world.biome.Biome;
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.common.config.Configuration;
 import net.minecraftforge.fml.common.FMLCommonHandler;
-import net.minecraftforge.fml.common.Loader;
 import net.minecraftforge.fml.common.Mod;
 import net.minecraftforge.fml.common.Mod.EventHandler;
 import net.minecraftforge.fml.common.SidedProxy;
@@ -57,6 +56,7 @@ import appeng.core.sync.network.NetworkHandler;
 import appeng.core.worlddata.WorldData;
 import appeng.hooks.TickHandler;
 import appeng.integration.IntegrationRegistry;
+import appeng.integration.IntegrationType;
 import appeng.recipes.CustomRecipeConfig;
 import appeng.recipes.CustomRecipeForgeConfiguration;
 import appeng.server.AECommand;
@@ -139,11 +139,6 @@ public final class AppEng
 	@EventHandler
 	private void preInit( final FMLPreInitializationEvent event )
 	{
-		if( !Loader.isModLoaded( "appliedenergistics2-core" ) )
-		{
-			AppEng.proxy.missingCoreMod();
-		}
-
 		final Stopwatch watch = Stopwatch.createStarted();
 		this.configDirectory = new File( event.getModConfigurationDirectory().getPath(), "AppliedEnergistics2" );
 		this.recipeDirectory = new File( this.configDirectory, "aerecipes" );
@@ -171,6 +166,11 @@ public final class AppEng
 			CreativeTabFacade.init();
 		}
 
+		for( final IntegrationType type : IntegrationType.values() )
+		{
+			IntegrationRegistry.INSTANCE.add( type );
+		}
+		
 		this.registration.preInitialize( event );
 
 		if( Platform.isClient() )