[tune] Tune Facelift (#2472)

This PR introduces the following changes:

 * Ray Tune -> Tune 
 * [breaking] Creation of `schedulers/`, moving PBT, HyperBand into a submodule
 * [breaking] Search Algorithms now must take in experiment configurations via `add_configurations` rather through initialization
 * Support `"run": (function | class | str)` with automatic registering of trainable
 * Documentation Changes

python/ray/tune/trial.py

@@ -95,7 +95,6 @@ class Trial(object):
         The args here take the same meaning as the command line flags defined
         in ray.tune.config_parser.
         """
-
         if not has_trainable(trainable_name):
             # Make sure rllib agents are registered
             from ray import rllib  # noqa: F401
@@ -267,8 +266,8 @@ class Trial(object):
                 self._status_string(),
                 location_string(
                     self.last_result.get(HOSTNAME),
-                    self.last_result.get(PID))),
-            '{} s'.format(int(self.last_result.get(TIME_TOTAL_S))),
+                    self.last_result.get(PID))), '{} s'.format(
+                        int(self.last_result.get(TIME_TOTAL_S)))
         ]
 
         if self.last_result.get("episode_reward_mean") is not None: