ref(controller): remove close_db_connection tests hack

The decorator once allowed us to work around issues with running
our test suite, but does not seem to be needed now.
fix(contrib/coreos): bump etcd peer heartbeat to 500ms
Merge pull request #1831 from carmstrong/etcd_500

fix(contrib/coreos): bump etcd peer heartbeat to 500ms
fix(scheduler): handle announcer timeouts to work around https://github.com/docker/docker/issues/8022
Merge pull request #1832 from gabrtv/announcer-timeout

fix(scheduler): handle announcer timeouts explicitly
Merge pull request #1830 from mboersma/remove-close-db-hack

ref(controller): remove close_db_connection tests hack
refactor(controller): the great celery purge
fix(scheduler): add gunicorn timeout for long-running methods
Merge pull request #1834 from gabrtv/purge-celery

Remove Celery from the Controller
chore(registry): bump version to v0.8.1
test(registry): remove unit tests

the unit tests are outdated, useless and consistently failing. We were
cloning and running the unit tests correctly some months ago, but now
it requires a local redis. Unit tests are covered by
docker/docker-registry, anyways.
Merge pull request #1838 from bacongobbler/bump-registry

chore(registry): bump version to v0.8.1
fix(client): use only stdout handler

If a warning message was logged, it would be logged to both stdout
and stderr. Using only the stdout handler will only log messages to
stdout.
ref(tests/etcdutils): optimize test-etcd Dockerfile

Reduces the virtual size of "deis/test-etcd" from 467.4MB to 200.8MB.
Merge pull request #1840 from mboersma/optimize-test-etcd

ref(tests/etcdutils): optimize test-etcd Dockerfile
Merge pull request #1839 from bacongobbler/fix-client-logging

fix(client): use only stdout handler
feat(database): use deis-store and WAL-e to ship WAL logs