fix discrete versions of kuka grasping environment

should fix issue 1386

examples/pybullet/gym/pybullet_envs/baselines/enjoy_kuka_grasping.py

@@ -12,7 +12,7 @@ from baselines import deepq
 
 def main():
     
-    env = KukaGymEnv(renders=True)
+    env = KukaGymEnv(renders=True, isDiscrete=True)
     act = deepq.load("kuka_model.pkl")
     print(act)
     while True:

examples/pybullet/gym/pybullet_envs/baselines/train_kuka_cam_grasping.py

@@ -25,7 +25,7 @@ def callback(lcl, glb):
 
 def main():
   	
-    env = KukaCamGymEnv(renders=True)
+    env = KukaCamGymEnv(renders=False, isDiscrete=True)
     model = deepq.models.cnn_to_mlp(
         convs=[(32, 8, 4), (64, 4, 2), (64, 3, 1)],
         hiddens=[256],

examples/pybullet/gym/pybullet_envs/baselines/train_kuka_grasping.py

@@ -25,7 +25,7 @@ def callback(lcl, glb):
 
 def main():
   	
-    env = KukaGymEnv(renders=False)
+    env = KukaGymEnv(renders=False, isDiscrete=True)
     model = deepq.models.mlp([64])
     act = deepq.learn(
         env,