Add two new regionExceptions: GMT and Europe/Nicosia

Currently, `getRegionForTimezone` fails for these two esoteric zones. I combed through the latest region files pretty thoroughly, and I think this accounts for all of them other than `US/Pacific-New`, which such an esoteric case that it has its own region file and I don't even want to bother with it ("it was not acted on by the Senate or signed into law by the President").