* Convert `_dependency_id` to `_dependency_ids`
Change `Job`s tracking from a single id of it's dependencies from a single _id_ to a list of _id_s. This change should be private to `Job` - especially leaving `Job#to_dict` and `Job#restore`s treatment of a single 'dependency_id' intact.
This change modifies existing tests.
* Remove reliance upon dependency property in tests
... use dependency.id not `_dependency_id`
* Re-add assertions for Falsey Values
* Add _dependency_id property
For backwards compatibility with other libs such as django-rq and rq-scheduler
* modify zadd calls for redis-py 3.0
redis-py 3.0 changes the zadd interface that accepts a single
mapping argument that is expected to be a dict.
https://github.com/andymccurdy/redis-py#mset-msetnx-and-zadd
* change FailedQueue.push_job_id to always push a str
redis-py 3.0 does not attempt to cast values to str and is left
to the user.
* remove Redis connection patching
Since in redis-py 3.0, Redis == StrictRedis class, we no longer
need to patch _zadd and other methods.
Ref: https://github.com/rq/rq/pull/1016#issuecomment-441010847
This includes:
- a partial refactor of the CLI to organize the shared options
- extends the tests in areas where passing custom backend classes makes sense
- allow setting the core CLI options as env vars
- minor cosmetic changes here and there