userportal,webadmin: fix documentation locale detection

- Fixed issue with locale detection using the URL path.

Change-Id: Iecb2708a201d94119db14521708bf53e42b6384d
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=885823
Signed-off-by: Alexander Wels <awels@redhat.com>