Rework AEItemStack (#3091)

* Use itemstack as itemdef
* HIGH_TAG/LOW_TAG should be compared both directions
* Remove getTagCompound
* Make Itemlist implementation independent
* Cache item id for performance reasons
* Add preconditions to saveguard against external meddling
* Chache itemDamage
* Remove IAEStackSearchKey for now, rename getDisplayStack

src/main/java/appeng/entity/EntityChargedQuartz.java

@@ -121,12 +121,12 @@ public final class EntityChargedQuartz extends AEBaseEntityItem
 					final ItemStack other = ( (EntityItem) e ).getItem();
 					if( !other.isEmpty() )
 					{
-						if( Platform.itemComparisons().isEqualItem( other, new ItemStack( Items.REDSTONE ) ) )
+						if( ItemStack.areItemsEqual( other, new ItemStack( Items.REDSTONE ) ) )
 						{
 							redstone = (EntityItem) e;
 						}
 
-						if( Platform.itemComparisons().isEqualItem( other, new ItemStack( Items.QUARTZ ) ) )
+						if( ItemStack.areItemsEqual( other, new ItemStack( Items.QUARTZ ) ) )
 						{
 							netherQuartz = (EntityItem) e;
 						}