Add MoveSomewhere inventory action

Improve shift+click experience

src/inventory.h

@@ -244,7 +244,13 @@ public:
 
 	// Move an item to a different list (or a different stack in the same list)
 	// count is the maximum number of items to move (0 for everything)
-	void moveItem(u32 i, InventoryList *dest, u32 dest_i, u32 count = 0);
+	// returns number of moved items
+	u32 moveItem(u32 i, InventoryList *dest, u32 dest_i,
+		u32 count = 0, bool swap_if_needed = true);
+
+	// like moveItem, but without a fixed destination index
+	// also with optional rollback recording
+	void moveItemSomewhere(u32 i, InventoryList *dest, u32 count);
 
 private:
 	std::vector<ItemStack> m_items;