CE-3030: Introduce flyway
Flyway has been introduced. Since it turned out that the correct migration scripts are the V5.2 and V6.2 versions, I deleted the V5.1 and V6.1, and renamed the correct scripts to V5 and V6.
Unfortunately, no version of H2 is compatible with the V1 migration script, so I thought we could temporarily disable Flyway in the tests. There is a recommended step in the release todos to restart the Flyway version with the current state, at that point we can re-enable Flyway in the tests.
Closes CE-3030