hghave: feature absence can be checked by prefixing with 'no-'
adding helloabort: '\n' and '\r' disallowed in filenamesadding helloabort: '\n' and '\r' disallowed in filenamesadding helloabort: '\n' and '\r' disallowed in filenamesadding helloabort: '\n' and '\r' disallowed in filenamesf hello hellof hello hello