Expose `--influx-{host, port, user, password}`.
Add optional bindings to `run_container{s}`.
Start up cAdvisor.
Syncing up with `master`.
Initial Heka config work.
`run_container`: Add support for port bindings.
`EC2Instance`: Reuse SSH and SFTP connections.
Launch Heka containers. Refactor options handling.

* Add `{Heka, Influx}Options`.
* Add `--heka-{host, port}` flags.
* Publish the Heka and cAdvisor ports for container status checks.
* Move `start_{cadvisor, heka}()` into `EC2Instance`.
* Add `EC2Instance#stop{cadvisor, heka}()`. Ensure `EC2Collection`
  stops Heka and cAdvisor on test completion.
* Add `EC2Instance#makedirs()` for recursively creating remote
  directories.
* `EC2Collection#wait_for_docker()` now only waits for Heka and
  cAdvisor to become available. `#start()` launches the containers.
Add `DockerDaemon#stop_container()`.
Create fresh SSH sessions for all interactions.

* Add `ssh.makedirs()`.
* Remove `EC2Instance#{makedirs, putfo}()`.
* Ensure the SSH and SFTP clients are closed after use.
Add `--{heka, influx}-secure`.

Ensure `EC2Collection#start_hekas()` formats IPv6 addresses correctly.
Remove unused imports and arguments.
Ensure `EC2Instance#connect()` does not block.

Execute all SSH client calls on a thread pool.
Wait for Heka and cAdvisor to start up.
Fix flake8 errors.
Syncing up with `master`.
Merge pull request #8 from kitcambridge/cadvisor-heka

Launch cAdvisor and Heka containers