SERIES PREMIERE: This new Fox series is co-created by Charlie Day, co-star and co-creator of FX’s long-running, long-raunchy It’s Always Sunny in Philadelphia. The pilot of this new series, though, is almost shockingly tame by comparison, and plays as a sitcom that could have been set in, and even written in, the era of The Golden Girls. This series is about a group of senior citizens at a retirement home, and to the extent that The Cool Kids is watchable, it’s because of the v