initial commit for reintroducing PyQT rendering

examples/play_model.py

 from flatland.envs.rail_env import RailEnv, random_rail_generator
 # from flatland.core.env_observation_builder import TreeObsForRailEnv
 from flatland.utils.rendertools import RenderTool
+from flatland.utils.render_qt import QtRailRender
 from flatland.baselines.dueling_double_dqn import Agent
 from collections import deque
 import torch
@@ -31,7 +32,8 @@ def main():
                 height=7,
                 rail_generator=random_rail_generator(cell_type_relative_proportion=transition_probability),
                 number_of_agents=1)
-    env_renderer = RenderTool(env)
+    # env_renderer = RenderTool(env)
+    env_renderer = QtRailRender(env)
     plt.figure(figsize=(5,5))
     # fRedis = redis.Redis()
 
@@ -101,7 +103,6 @@ def main():
                 score += all_rewards[a]
 
             env_renderer.renderEnv(show=True, frames=True, iEpisode=trials, iStep=step)
-            sEnv = fR.set("RailEnv0")
 
             obs = next_obs.copy()
             if done['__all__']: