Fix m.route() tests
Fix m.route() tests

- Wasn't calling route.prefix(), was assigning to it
- Needed to handle pushstate prefix (`""`) specially in assertions

impinball/mithril.js,lhorie/mithril.js,barneycarroll/mithril.js,tivac/mithril.js,impinball/mithril.js,pygy/mithril.js,MithrilJS/mithril.js,pygy/mithril.js,lhorie/mithril.js,MithrilJS/mithril.js,tivac/mithril.js,barneycarroll/mithril.js