Convert Unity.py Application Package API to use Hosted Workflows

[mcduffie]

Currently the Unity.py access to Dockstore API uses deprecated end points. Convert to use Dockstore Hosted Workflows.

• These series of tests may be useful to see how to use hosted workflows in an automated way.
• Example of editing files using the API
• Description on the difference between tools and workflows
• Confusing aspect of the API: Dockstore calls them "tools" in the UI and the doc, but the API for accessing those tools instead uses the word "containers" in the endpoint
• According to Denis Yuen: “if your group does end up sticking with manual registration let us know. Deprecating manual registration is still in the planning stages and not a near term priority. We could consider something like limit manual registration to administrators or power users, or remove/deprecate the UI portion only.“

Acceptance Criteria:

• Unity.py updated to allow programmatic management of hosted workflows in Dockstore
• Hosted workflow created can be extracted for running in SPS

[mliukis]

From team meetings:
* Modify application_service in unity-py code to support hosted workflows using the Dockstore API #hosted API
* Use tutorial notebook as example to get started with (dockstore publish example notebook)
* Modify register() and unregister methods to use hosted workflows

[rtapella]

Should this be in the unity-py repo?

[rtapella]

Ideally we can use some "standardized" language in the unity.py API that isn't necessarily the same as the tools vs. containers vs. workflows that are used in Dockstore.

[rtapella]

is the application_descriptor.json thingy part of this work as well?