Add ability to look up and down in bubble view

[framed]

Currently you can only "look" left and right in bubble view. To make this functionality more useful the user needs to be able to look up and down also, with the camera/eye position remaining static.

[daniel]

Yes I tried to implement something like that but the result was giving "seasickness" ;).

I just have to try again and find a good way to implement it.

[daniel]

After a long wait, this has been eventually fixed! It will be available in the next version (2.7)