(WIP) address gh-146, gh-118 -- validate notification rules, improve API error checking
rule validation, more work on time restrictions etc.

WIP -- there's still one failing test which needs some time zone
behaviour debugging.
data validation bug fixes
pass duration when creating ice_cube schedule, fix occuring_at?
Merge branch 'master' of github.com:flpjck/flapjack into 146_validate_notification_rules
Remove unneeded log statement
Merge branch '146_validate_notification_rules' of github.com:ali-graham/flapjack into 146_validate_notification_rules
Cleanup (time_zone -> timezone, optional for rule validation)

Also fixed a couple of the rule validations.
Merge branch 'master' of github.com:flpjck/flapjack into 146_validate_notification_rules
Merge branch '146_validate_notification_rules' of github.com:ali-graham/flapjack into 146_validate_notification_rules
remove timezone from most notification rule operations, not needed
Merge branch '146_validate_notification_rules' of github.com:ali-graham/flapjack into 146_validate_notification_rules
fix timezone handling when filtering events with notification rules with time restrictions
Merge pull request #167 from jessereynolds/146_validate_notification_rules

146 validate notification rules - timezone fixes