Cleanup imports.

Till now, most of the modules were importing all of the module objects
(variables, classes, functions, other imports) into module namespace,
which potentially could (and was) cause of unintentional use of class or
methods, which was indirect imported.

With this patch, all the star imports were substituted with top-level
module, which provides desired class or function.

Besides, all imports where sorted (where possible) in a way pep8[1]
suggests - first are imports from standard library, than goes third
party imports (like numpy, tensorflow etc) and finally coach modules.
All of those sections are separated by one empty line.

[1] https://www.python.org/dev/peps/pep-0008/#imports

environments/environment_wrapper.py

@@ -13,14 +13,14 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
-
-import numpy as np
-from utils import *
-from configurations import Preset
-from renderer import Renderer
 import operator
 import time
 
+import numpy as np
+
+import renderer
+import utils
+
 
 class EnvironmentWrapper(object):
     def __init__(self, tuning_parameters):
@@ -50,7 +50,7 @@ class EnvironmentWrapper(object):
         self.height = 1
         self.is_state_type_image = True
         self.measurements_size = 0
-        self.phase = RunPhase.TRAIN
+        self.phase = utils.RunPhase.TRAIN
         self.tp = tuning_parameters
         self.record_video_every = self.tp.visualization.record_video_every
         self.env_id = self.tp.env.level
@@ -62,7 +62,7 @@ class EnvironmentWrapper(object):
         self.wait_for_explicit_human_action = False
         self.is_rendered = self.is_rendered or self.human_control
         self.game_is_open = True
-        self.renderer = Renderer()
+        self.renderer = renderer.Renderer()
 
     @property
     def measurements(self):