Add spell quick access keys

src/main/java/electroblob/wizardry/item/ISpellCastingItem.java

@@ -65,6 +65,16 @@ public interface ISpellCastingItem {
 		// Nothing here either
 	}
 
+	/**
+	 * Selects the spell at the given index bound to the given itemstack. The given itemstack will be of this item.
+	 * @param stack The itemstack to query.
+	 * @param index The index to set.
+	 * @return True if the operation succeeded, false if not.
+	 */
+	default boolean selectSpell(ItemStack stack, int index){
+		return false;
+	}
+
 	/**
 	 * Returns whether the spell HUD should be shown when a player is holding this item. Only called client-side.
 	 * @param player The player holding the item.

src/main/java/electroblob/wizardry/item/ItemWand.java

@@ -113,6 +113,11 @@ public class ItemWand extends Item implements IWorkbenchItem, ISpellCastingItem,
 		WandHelper.selectPreviousSpell(stack);
 	}
 
+	@Override
+	public boolean selectSpell(ItemStack stack, int index){
+		return WandHelper.selectSpell(stack, index);
+	}
+
 	@Override
 	public boolean showSpellHUD(EntityPlayer player, ItemStack stack){
 		return true;