Add rudimentary file transfer capability
Add rudimentary file transfer capability

- We want to include a number of ordinary files in the data sync.

- The dbms type "files" leads to compress/push/pull/decompress a
  directory provided as "database" argument.

solo @schmie

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet