def method_missing(m, *args)
      res = @targets.inject([]) { |res, t| res << t.send(m, *args) }
      res[0]
    end
def method_missing(m, *args)
      res = @targets.inject([]) { |res, t| res << t.send(m, *args) }
      res[0]
    end
Forward any method invocation to targets

 === Parameters
 m(Symbol):: Method that should be multiplexed
 args(Array):: Arguments

 === Return
 res(Object):: Result of first target in list