Added regex support for notification rule tags.

Only do regex comparison if the tag starts with 'regex:'.
Added new regex_tags key for notification rule and use that for regex
matching.
Merge branch 'regex_support_for_tags2' of git://github.com/jswoods/flapjack into jswoods-regex_support_for_tags2
simplify the data being tested to aid debugging
fix failing tests
remove debugging from notification_rules.feature