Flyway Integration into subproject adapter-persistence-jpa

[eamtalu]

Flyway Integration int subproject adapter-persistence-jpa:

• Configured Root build.gradle for flyway
• Added flyway into the subproject adapter-persistence-jpa
• Configured build.gradle into adapter-persistence-jpa for flyway task
• Offloaded hibernate schema creation to flyway, keeping hibernate only for schema validation whereas flyway for schema migration(naming convention: V1__.sql)
• Updated build.gradle in adapter-persistence-jpa so that test depends on flyway migration first.
• Updated ReadMe File for flyway operation.

[valentinajemuovic]

Thanks @eamtalu!