couchdb service should not require on soledad

The couchdb service should not always also require the soledad service. This breaks our quickstart tutorial, but also, some providers don't ever need soledad.

site_couchdb/manifests/create_dbs.pp:

  ## shared database
  ## r/w: soledad
  couchdb::create_db { 'shared':
    members => "{ \"names\": [\"${site_couchdb::couchdb_soledad_user}\"], \"roles\": [\"replication\"] }",
    require => Couchdb::Query::Setup['localhost'],
    notify  => Service['soledad-server'];
  }

(from redmine: created on 2016-12-18, closed on 2016-12-20)