MBS-6352 Implement `./admin/ExportAllTables --check-completeness` and add more missing tables
First steps for this
Finishes adding the cover art origin to the sidebar
Merge remote-tracking branch 'luks-bitbucket/MBS-6352' into beta

* luks-bitbucket/MBS-6352:
  MBS-6352 Implement `./admin/ExportAllTables --check-completeness` and add more missing tables
Merge remote-tracking branch 'reosarevok-bitbucket/mbs-5911' into beta

* reosarevok-bitbucket/mbs-5911:
  Finishes adding the cover art origin to the sidebar
  First steps for this