Another landmark from Boston Lyric Opera
David Kravitz welcomes strange travelers to his table in Clemency. Photos: Eric Antoniou.If you haven't been keeping up with Boston Lyric Opera's traveling "Annex" productions, then I'm afraid you've been missing out on the most challenging opera the city has to offer. (Perhaps that it has ever had to offer.) The three previous annex productions - The Turn of the Screw, The Emperor of Atlantis, and T…