installation: fix for inversed user/database name
installation: fix for inversed user/database name

* Addresses an issue with inversed user and database name in
  `inveniomanage database init` command.

Signed-off-by: Alessio Deiana <e9659f8978a9408eccc7316f742696808c730d32@cern.ch>
Reviewed-by: Samuele Kaplun <2e218f779e12714c314fad8ebf6b3041daa21337@cern.ch>

tiborsimko/invenio,inveniosoftware/invenio,inveniosoftware/invenio,tiborsimko/invenio