Remove external configuration #8
Description
It only has two values and:
- Defaulting the showTimestamps flag makes no sense
- Storage was migrated to Sqlite (Implement update, delete #2), and the sqldelight library does not support changing the database file location. The only place where the json file will be used is in the upcoming import-export feature (Implement import (+ export?) #7), and it should be better to read from a single location, the user directory.