Add test case for inheritance of enums (to be sure how it works).
Implement a public function to compare the document content ignoring
the metafields.
Do not overwrite design documents from feat-dbload.

* Debug verbosily about what changes are to be deployed.
* This responsibility is to be moved to "feat-service upgrade" command.
Implement IDatabaseClient.copy_document() method.

This is necessary to implement the live view update.
Implement "feat-service upgrade" operation.

Update the couchdb views, wait for reindex them, and restart.