Integrate Dockstore API into unity-app-generator

[mcduffie]

Modify requirements.txt pull in unity-py to the Python environment.

Modify process_repo.py to use dockerurl from previous steps along with repository name to call the Dockstore hosted workflow registration process of unity-py.

Acceptance Criteria

• Dockstore API work from Convert Unity.py Application Package API to use Hosted Workflows unity-ads-deployment#87 called by script
• Example application tested

[mcduffie]

Implemented at 5d60ece