Switch Dockerfile to UBI 8 Python 3.8 image

• Move various command to entrypoint script to avoid assumption of having direct database access during image build. Additionally, switch from mod_wsgi to gunicorn.
• Flatten repository structure
• Replace httpd with nginx
• Add docker-compose for local development
• Recreate migration files as they were failing on the empty database
• Add commits with mass-changes to .git-blame-ignore-revs