Undertow file and exists predicates do not work in EAP 7.0.0

Issue

• We try to use a undertow handler with the file or exists predicates to do a redirect but they don't work. We've tried redirects like the following in our app's WEB-INF/undertow-handlers.conf, but file always resolves to false and exists always resolves to true:

not file(%U) -> redirect('/index.html')
not exists(%U) -> redirect('/index.html')