Show Exit button when in Borderless or Fullscreen about vignette

[LeNitrous]

Not sure if this looks okay but this is what it looks like when in fullscreen. Notice how the banner/header gets pushed down which shows a gap which looks odd. Not sure about this. @sr229 your thoughts?

[sr229]

I think we just block people entering fullscreen altogether might be a better option but if you want to proceed with this, make sure that only appears on Borderless and Fullscreen mode.

[LeNitrous]

I don't think its a good idea to get rid of the option. I'll keep this as is since it doesn't really look that out of place after all.