[FIX] forums: Move smart quote cleaning as is apparently prevents HTMLPurifier functioning properly on some systems

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/13.x@52861 b456876b-0849-0410-b77d-98878d47e9d5
[MRG] Automatic merge, branches/13.x 52857 to 52861

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@52862 b456876b-0849-0410-b77d-98878d47e9d5