[FIX] switch lang: Don't lose the beginning of the url if it's a category sefurl (thanks Bernard)

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@50508 b456876b-0849-0410-b77d-98878d47e9d5
a few fixes

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@50511 b456876b-0849-0410-b77d-98878d47e9d5