Removed not-very-expressive "This is the gate..." welcome messages on those admin splash pages that still had it, in order to standardize this across all the modules.  (The admin interfaces should be generally improved later when the admin pages are moved onto the new URL schema.)
Removed not-very-expressive "This is the gate..." welcome messages on
those admin splash pages that still had it, in order to standardize
this across all the modules.  (The admin interfaces should be
generally improved later when the admin pages are moved onto the new
URL schema.)

tiborsimko/invenio-formatter,tiborsimko/invenio-formatter,tiborsimko/invenio-formatter,inveniosoftware/invenio-formatter,inveniosoftware/invenio-formatter,inveniosoftware/invenio-formatter