[Tune] Access trial name from within trainable class

It would be useful to be able to access the trial name from within a Trainable.

Current solution:

class RayWorker(tune.Trainable):
    def _setup(self, config):
        self.trial_name = self._logdir.split('/')[-1].split('_')[0]

However this will only work when the default logging setup is used

[richardliaw]

You can now access the trial name in the trainable.

[LianShuaiLong]

you can access trial name via self.trial_name

cool!!!