Add dbmigrations to the docker build.

Dependencies

• [2] SOIAMXLW Build versioned docker images.
• [*] 4ZLEDBK7 Initial attempts at dockerizing, cabal isn't cooperating.
• [*] 7VGYLTMU Clean up schema version handling.
• [*] HO2PFRAB Client login now handles response correctly.

Change contents

• edit in Dockerfile at line 58
  [5.222]

  [5.222]
  + ADD ./migrations /opt/aftok/migrations
• edit in Dockerfile at line 73
  [2.288]

  [6.828]
  +

  + WORKDIR /opt

  + RUN stack install dbmigrations