Added special treatment for CFG_SITE_SECURE_URL that may be empty, in which case it is put equal to CFG_SITE_URL.
Added special treatment for CFG_SITE_SECURE_URL that may be empty, in
which case it is put equal to CFG_SITE_URL.

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