/**
* <summary>Deletes a given inventory item instance, provided it is a part of this collection</summary>
* <param name="invInstance">The inventory item instance to delete</param>
* <param name="amount">The amount to delete</param>
*/
public void Delete(InvInstance invInstance, int amount)
{
if (invInstances.Contains(invInstance))
{
invInstance.Clear(amount);
Clean();
PlayerMenus.ResetInventoryBoxes();
}
}