Add permissions sql file and PermissionEntity class
Adding permission queries and `PermissionService`
Add `PermissionServiceTest`
create `Permission` class and add a list of them to `Conference`
 - The soon to be renamed `ConferenceFetchProcess` now grabs a list of them from the DB and adds to `Conference`
Adding tests for `ConferenceFetchProcess`
Various things:
- preventing NPE in `Conference` when database permissions are null/empty
- fixing compiler errors
Renaming `ConferenceFetchProcess` to `RetrieveConferenceProcess`
Build out `ConferenceUpdateProcess` to store permissions on conference updates
Cleanup tests
Add functionality to save conference owners permission on create new conference endpoint
Adding a database enum for levels of permission
 - requires a new converter to be registered in `SqlConnectionProducer`
 - also registering converters in tests now
 - Changing data type on `Permission` and `PermissionEntity` from `String` to `PermissionLevel`