With this, I intend to make it clearer that Auto, Force 4:3, Force 16:9
and Custom are really the same thing, just with the aspect ratio of the
simulated TV being selected in a different way. I also extended the
introduction in a way I feel will clarify things but which you are
welcome to bikeshed :)
I was thinking of this during the review of 41b19e262f, but wanted to
put it in a separate PR as to avoid blocking it on bikeshedding.
I'm a bit unsure what to do about the word "analog" in "analog TV". I
felt that repeating it for each of these options would be too
repetitive. I suppose there's a reason why we used the word originally,
but digital TVs do give you basically the same aspect ratio for GC/Wii
games as analog TVs. (Of course, whether it's 4:3-like or 16:9-like
depends on what aspect ratio you set in the TV's settings, but that's
the case for widescreen CRTs too.)