Remove API Url link from header on Access Denied page

Closes COUCHDB-2436
Unify one_pane and one_pane_db again

We recently introduced a new template `one_pane_db` which had
the rightHeader for the list of DBs. In retrospective it turns
out that also other views need the rightHeader markup to
populate it with elements.

Views that don't need the rightHeader element should not get
influenced so this removes some complexity and avoids that the
templates diverge more in the future.
Replicate icon on Databases page now redirects properly

Closes COUCHDB-2437
Fix path for ZeroClipboard

If deployed as an CouchApp, the path for ZeroClipboard did not
match

Steps to reproduce:
 - run `grunt couchapp_deploy` with a Couch in Admin-Party
 - open http://localhost:5984/fauxton/_design/fauxton/index.html

Closes COUCHDB-2323