Require Tornado < 5
Require Tornado < 5

Tornado 5 requires Python >= 2.7.9 because of improvements made to the
`ssl` module in that version. Mopidy probably works with Tornado 5, but
to keep tests running with Python 2.7.6 on Travis CI we don't support
Tornado 5 for now.

mopidy/mopidy,jodal/mopidy,jodal/mopidy,adamcik/mopidy,jcass77/mopidy,adamcik/mopidy,mopidy/mopidy,kingosticks/mopidy,adamcik/mopidy,jcass77/mopidy,mopidy/mopidy,kingosticks/mopidy,jodal/mopidy,jcass77/mopidy,kingosticks/mopidy