make mochifmt use mochinum only when available
make mochifmt use mochinum only when available

git-svn-id: 873206019493e617559b0c84a00ebf9b834e1e55@68 583d1f64-3c3e-0410-8459-0f15fcd77d59

toddlipcon/mochiweb,asceth/mochiweb,clones/mochiweb,mrkurt/mochiweb,abhay/mochiweb.old,davidw/mochiweb