[FIX] Text field validation in trackers was only done client side

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/13.x@52253 b456876b-0849-0410-b77d-98878d47e9d5
[FIX] login: Cope with strange edge case in IE where the $_SESSION['loginfrom'] is the non-sefurl url, even though sefurl is enabled, leading to a 403 error when the page= param ends up being empty but still on the request

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/13.x@52256 b456876b-0849-0410-b77d-98878d47e9d5