Update Glider DAC application architecture

[benjwadams]

1. Update Glider DAC to use the application factory pattern: https://flask.palletsprojects.com/en/2.2.x/patterns/appfactories/
   This makes testing and refactoring the application much easier.

2. Move away from MongoDB and BerkeleyDB to a relational database by using SQLAlchemy.

These are already well underway on this branch:
https://github.com/benjwadams/glider-dac/tree/application_factory_fixes_rebase

1. Is basically finished at this point.
2. Is well underway but needs further testing and migration scripts need to be reinstated.

[sarinamann-noaa]

Will discuss to determine if this fits within new BIL

[sarinamann-noaa]

Priority after hurricane season- upgrade slated to take place and resolve this