Restore DBS Url in CouchDB

Also fix the issues with the DBSUrl and the clone API

Fixes #4498
Merge pull request #4515 from dballesteros7/DBSUrl-will-be-back

Restore DBS Url in CouchDB
0.9.54

Signed-off-by: Zdenek Maxa <zdenek.maxa@cern.ch>