1. Rewrite services using sqlite(which supports async-await) rather than sqlite3;
2. Write the logic for ScheduleReminder and SendReminder;
3. Write the logic for authorization and permission judgement;
4. Fix the logic of currently malfunctioning services.
APIs:
[x]initialize
[x]addUser
[x]addTask (partial: need to fix output taskID)
[ ]showTasksByDate
[x]deleteTask
[x]loginUser
[x]changePassword
[x]scheduleReminder
[x]sendReminder
[x]checkUser
Bare bones