[V20.7 - Air Combat] Cannot cancel retreat even when having enough fuel

Steps to reproduce:

- enter air combat

- click outside the combat area to initiate retreat

- change your mind, start clicking anywhere inside the combat area, click the retreat icon, click anywhere, nothing cancels the retreat, despite the retreat icon tooltip claiming it is possible to cancel retreat if there's enough fuel

This is especially annoying if the retreat path turns out to lead dangerously close to any UFO (the automatic retreat due to low fuel is so dangerous because of this that it's usually better to let the fighter continue the combat, since it'd be lost one way or another, but if it stays, it at least can deal some more damage).

Ok, I found http://www.goldhawkinteractive.com/forums/showthread.php/7719-fleein-aerial-combat , which says that clicking on any UFO cancels the retreat. That works, but it's very non-intuitive.

This is especially annoying if the retreat path turns out to lead dangerously close to any UFO (the automatic retreat due to low fuel is so dangerous because of this that it's usually better to let the fighter continue the combat, since it'd be lost one way or another, but if it stays, it at least can deal some more damage).

Thinking of this, my suggestion for improving the automatic retreat on low fuel would to allow redirecting the retreating aircraft anywhere outside of the combat area, so that some maneuvering would be still possible by selecting where to retreat to (and again change it if some UFO starts getting too close). This could be exploited to keep the aircraft longer in the combat and still fire cannons (which apparently happens according to the retreat button tooltip), but that could be avoided by disabling any firing during retreat (it's retreating, after all).