[rllib] Also refactor DQN to use shared RLlib models (#730)

* wip

* works with cartpole

* lint

* fix pg

* comment

* action dist rename

* preprocessor

* fix test

* typo

* fix the action[0] nonsense

* revert

* satisfy the lint

* wip

* works with cartpole

* lint

* fix pg

* comment

* action dist rename

* preprocessor

* fix test

* typo

* fix the action[0] nonsense

* revert

* satisfy the lint

* Minor indentation changes.

* fix merge

* add humanoid

* initial dqn refactor

* remove tfutil

* fix calls

* fix tf errors 1

* closer

* runs now

* lint

* tensorboard graph

* fix linting

* more 4 space

* fix

* fix linT

* more lint

* oops

* es parity

* remove example.py

* fix training bug

* add cartpole demo

* try fixing cartpole

* allow model options, configure cartpole

* debug

* simplify

* no dueling

* avoid out of file handles

* Test dqn in jenkins.

* Minor formatting.

* fix issue

* fix another

* Fix problem in which we log to a directory that hasn't been created.

test/jenkins_tests/run_multi_node_tests.sh

@@ -69,3 +69,7 @@ docker run --shm-size=10G --memory=10G $DOCKER_SHA \
     python /ray/python/ray/rllib/evolution_strategies/example.py \
     --env-name=Pendulum-v0 \
     --iterations=2
+
+docker run --shm-size=10G --memory=10G $DOCKER_SHA \
+    python /ray/python/ray/rllib/dqn/example-cartpole.py \
+    --iterations=2