Refactor

[sei-jbooz]

1. Adds doc strings and typehints to all functions
2. Remove functions.py in place of several other files
   a. Database functions have their own file
   b. Grading functions have their own file
   c. Cron function have their own file
   d. Service log functions are moved alongside other service/logging functions
   e. Rename the flask config to be more explicit
3. Refactors read_config and globals to be centralized with sensible defaults in place
4. Adds debug logging options and command line arguments to specify the desired log level