But nothing ends anymore, you know that. I was a fan of “Community,” the Dan Harmon sitcom that, with its imaginative leaps and meta sensibility, was fresh and funny. It ended in 2015, after six seasons, five on NBC and one on Yahoo’s now-defunct streaming service. Your TV GPS, Globe TV critic Matthew Gilbert’s look at the week ahead in television, appears every Monday morning on BostonGlobe.com . Today’s column covers Oct. 3-9 And so, after years chanting the show’s “six seasons and a movie” catchphrase, there will finally be a movie. Peacock has announced that it has greenlit a...