Enhancement: Allow the window in all scenes

[Atario]

Currently, the window can't be opened when not in control of a vessel — in Space Center, and some other scenes. This makes some sense, since when this is the case, there's no targeting to set. However, the other functions (Control Vessel button, etc.) would still be useful in these situations. Instead of disabling the whole window, it would be nice to only hide the targeting buttons in this state but still allow the window.

[hashashin]

Sorry I missed this. That should be doable, but I don't have the time right now. However, I would gladly accept a pull request.

Salud.