Drop unsused "extras" dependency

Change-Id: I9264d983f809fafa249536f1b321ee1db02aad4d
Introduce database functionality into KDS

Add database setup and initial testing into Key Distribution Server.
Also adds a migration script.

Implements: bp key-distribution-server
Change-Id: I22e914ef1ca6ec8217d131c073261b309d9f637e
Merge "Drop unsused "extras" dependency"
Merge "Introduce database functionality into KDS"