* Avoid warning about swap being unlimited
Currently we get the following message on Jenkins:
"Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap."
Since we're not limiting swap anyway, we might as well avoid trying to.
https://docs.docker.com/config/containers/resource_constraints/#--memory-swap-details
* Fix escaping in re.search()
* Fix escaping in _noisy_layer()
* Raise a more descriptive error when dashboard data isn't found
* Don't error on dashboard files not being found when webui isn't required
* Change dashboard error to a warning instead
* Remove all __future__ imports from RLlib.
* Remove (object) again from tf_run_builder.py::TFRunBuilder.
* Fix 2xLINT warnings.
* Fix broken appo_policy import (must be appo_tf_policy)
* Remove future imports from all other ray files (not just RLlib).
* Remove future imports from all other ray files (not just RLlib).
* Remove future import blocks that contain `unicode_literals` as well.
Revert appo_tf_policy.py to appo_policy.py (belongs to another PR).
* Add two empty lines before Schedule class.
* Put back __future__ imports into determine_tests_to_run.py. Fails otherwise on a py2/print related error.
