For native fullscreen, simply remove the custom animation as it doesn't
look good and doesn't look native. This was added back when resizing the
window rapidly would result in artifacts, but they should have all been
fixed. As such, no need to hide everything under a black fade.

TODO:
- Closing windows while in native fullscreen doesn't work
- Investigate if I can give a "no-animation" option.

- Test / TODO:
  - Border-less -> full screen (success and fail)
  - Look into fuopts
  - Clean up misc cleanups like didFailTOExit has a lot of junk there
  - Decide on orderOut vs close.
  - Look into the whole maximizeWindow commented out shit
  - Cmd-N while in full screen already doesn't work.

For custom fullscreen, make it so that if `MMFullScreenFadeTime` is set
to 0 (which is now the default), the fading animation will simply not be
drawn as it simply flickers. Since it now defaults to 0, the user will
have to manually set this back to 0.25 to get the old functionality,
which is ok as it's somewhat a legacy feature anyway and there shouldn't
be any flickering now during the transition.

Also, update documentation on full-screen to provide more info on native
vs custom, and clean up old outdated texts.

Misc driveby fixes related to full screen:
- Robustify the Touch Bar full screen button to listen to `OptionSet`
  event which is more robust than relying on `VimResized`, which also
  didn't work when 'fuoptions' is set to nothing.
- Make MacVim handle the DidFailToEnter/ExitFullScreen events better.
  These events could fire when using native full screen while the user
  is e.g. switching space. We need to make sure to properly update the
  states when these two events happen and let Vim know what the current
  `'fullscreen'` state is so both sides are synced.
- Fix up the preferences pane's full screen buttons to not trigger
  fontPropertiesChanged which was a mistake due to copy-and-paste in
  Interface Builder.

See:
- macvim-dev#292 / macvim-dev#289 which implemented the fade effect.

For native fullscreen, simply remove the custom animation as it doesn't
look good and doesn't look native. This was added back when resizing the
window rapidly would result in artifacts, but they should have all been
fixed. As such, no need to hide everything under a black fade.

For custom fullscreen, make it so that if `MMFullScreenFadeTime` is set
to 0 (which is now the default), the fading animation will simply not be
drawn as it simply flickers. Since it now defaults to 0, the user will
have to manually set this back to 0.25 to get the old functionality,
which is ok as it's somewhat a legacy feature anyway and there shouldn't
be any flickering now during the transition.

Also, update documentation on full-screen to provide more info on native
vs custom, and clean up old outdated texts.

Misc driveby fixes related to full screen:
- Robustify the Touch Bar full screen button to listen to `OptionSet`
  event which is more robust than relying on `VimResized`, which also
  didn't work when 'fuoptions' is set to nothing.
- Make MacVim handle the DidFailToEnter/ExitFullScreen events better.
  These events could fire when using native full screen while the user
  is e.g. switching space. We need to make sure to properly update the
  states when these two events happen and let Vim know what the current
  `'fullscreen'` state is so both sides are synced.
- Fix up the preferences pane's full screen buttons to not trigger
  fontPropertiesChanged which was a mistake due to copy-and-paste in
  Interface Builder.

See:
- macvim-dev#292 / macvim-dev#289 which implemented the fade effect.