Changed to-list! to "Collects results lazily, makes efficient use
    of the the lazy nature of pipes/gremlin graph walking."

    Note, this causes two tests to fail.  I then added two equivalent
    tests which have been modified slightly and now pass. I believe
    this is really a design decision.

    See test/ogre/branch/if_then_else_test.clj and the function
    show-the-problem-above for some "discussion" of this issue.