API OpenBackpack


 * OpenBackpack opens the backpack if it was not already open, or sets a flag to affect CloseBackpack
 * CloseBackpack closes the backpack unless it was already open before OpenBackpack was called

backpackWasOpen = OpenBackpack CloseBackpack

Returns

 * backpackWasOpen : Boolean (1 or nil) - Evaluates to true if OpenBackpack detected the backpack was already open and will prevent CloseBackpack from acting