configfile: added options.no_watch, skip watch when no cb

* add a missing semicolon
* added options.no_watch
* if there's no callback, don't watch the config file (pointless)
* a potential fix for Issue #621, assuming I guessed Steve's intent correctly
configfile: s/jslint/jshint/
Merge pull request #630 from msimerson/configfile

configfile: added options.no_watch, skip watch when no cb