Added resque dependencies.
Stub out the queue worker for ingesting bags.
Started the class Aptrust::S3Poll.

Currently, it just reads the config for the institutions. The file
`config/institutions.yml.local` has a template for the information
needed for each institution.
Added config to get the URL of the Redis server.
Put incoming bags into the right queue.

Also tweaked the API for the worker stub.
Put most of the S3 polling worker into place.

* Backing off from polling every minute to once a day;
* Reading configuration from the environment (and figaro) and
  `config/institutions.yml`;
* Connect to the various servers; and
* Poll each bucket and enqueue any tar files found.
Added a Rake task to run the S3 polling worker.
Added a Procfile to bootstrap the system.
Complicated the history checking algorithm.

Still isn't right, though. Getting ready to rip it out by the roots.
Use date stamps to identify new bags.

Also removed printf-debugging.
In which I almost use globals...

... and writhe in self-loathing.
Finished stubbing out the bag ingest worker.

* Added an entry in the `Procfile`; Added a rake task (`bag:work`); and
* Finished the stub task that deletes the bag being ingested.
rails generate model ingest_job
Added a few columns to ingest_jobs.
Insert ingest job information into ActiveRecord.
Use the rails logger.
Added a little documentation.
Be a little defensive about logging.
Display basic information about the last 10 jobs.
More messages from servers.