When it comes to movies, the official kickoff for fall is the Toronto International Film Festival, a glitzy gala where Oscar hopefuls have their premieres and the industry flocks to find out what titles are going to be talked about in the coming season. And, usually, this means a procession of sober, adult movies about sober, adult topics. Feature films steeped in things like unfettered joy, laughter, glee — you know, fun — are usually abandoned to the studio blockbusters of the summer and spring, and winter. But not this year. If the just-concluding TIFF is any indication, this year has the potential for being the most upbeat awards season in ages.