Add database schema, remove old code, refactor asynctask
Summary:
Remove unreachable code
Remove useless AsyncTask
Replace asynctask with coroutine, merge inside FragmentHelper
Fix T1429
Test Plan: Search for stop name (like, "marc" or "cast") in previous version and check that the results are the same in this diff
Reviewers: Libre BusTO hackers, valerio.bozzolan
Reviewed By: Libre BusTO hackers, valerio.bozzolan
Subscribers: valerio.bozzolan
Project Tags: Libre BusTO
Maniphest Tasks: T1429
Differential Revision: https://gitpull.it/D240