Add small plugin for Erebus. (possibly to be expanded)

src/main/java/forestry/plugins/PluginManager.java

@@ -89,6 +89,7 @@ public class PluginManager {
 		BIOMESOPLENTY(new PluginBiomesOPlenty()),
 		CHISEL(new PluginChisel()),
 		ENDERIO(new PluginEnderIO()),
+		EREBUS(new PluginErebus()),
 		EXTRAUTILITIES(new PluginExtraUtilities()),
 		GROWTHCRAFT(new PluginGrowthCraft()),
 		HARVESTCRAFT(new PluginHarvestCraft()),