Bayer Leverkusen are setting their sights on a title treble now that they have one hand on the Bundesliga trophy and the German Cup final is still several weeks away. Xabi Alonso’s team takes an unbeaten run of 41 matches into their Europa League quarter-final first leg match on Thursday against West Ham United. Leverkusen are expected to have clinched a maiden Bundesliga title by the time of the second leg of the tie in London on April 18. A 1-0 victory at Union Berlin on Saturday, coupled with another Bayern Munich setback in the form of a 3-2 defeat in Heidenheim, means that Leverkusen will…