* Introduced `MonitoringWorkflowExecuter` and `edera.monitoring`:
- Allows workflow executors to report information about tasks
- Allows you to aggregate this information over sources and time, and render it as an HTML
* Added a separate "offline" workflow to the daemon (useful to run monitor watchers)
* Re-worked the `Storage` interface
* Replaced DOA `ZooKeeperStorage` with more efficient MongoDB-based `MongoStorage`
* Refactored duplicating tests (`pytest` is really full of magic)
* Reorganized tests that involve external services (like ZooKeeper or MongoDB):
- Such tests became optional
- No test harnesses - only real service instances
- Now you need to redefine corresponding environment variables in `tox.ini`
* Simplified class factory declarations (like `Qualifier`s)
* Fixed a couple of minor bugs
* Fixed documentation