webui: menu and navigation fixes
1. When navigation is initiated from clicking and a link with hash, update
of facet state causes that subsequent click on a link with hash will be
ignored. Caused by a code which prevents infinite loop because of facet
state update. Now hash update is done only if it was really changed.
2. registered correct handler for standalone pages
3. fix selection of menu item where the items differ only in args. Chooses
the item with the most similar state to current facet.
Reviewed-By: Martin Kosek <firstname.lastname@example.org>
Reviewed-By: Tomas Babej <email@example.com>