* Properly mark hosts with failures in includes as failed
* Don't send callbacks until we're sure we're done, and also fix how
we increment stats so failures don't show up as ok's
* Fix a bug in the include file logic where a failed include could lead
to an infinite loop in the task iteration logic
Fixes#12933
* When iterating over a child state, a failure should be propagated
up so parent blocks don't continue iterating
* Make sure a child state exists before trying to search it
Fixes#12210
Replace .iteritems() with six.iteritems() everywhere except in
module_utils (because there's no 'six' on the remote host). And except
in lib/ansible/galaxy/data/metadata_template.j2, because I'm not sure
six is available there.
* added pattern matching to match v1 functionality
* check the task name, not the task+role name for matches
* make sure the input is unicode
Fixes#11692
Also making PlayContext a child class of the Playbook Base class,
which gives it access to all of the FieldAttribute code to ensure
field values are correctly typed after post_validation
Fixes#11381
There was a confusion between the valid values for defaults.gathering
(explicit/implicit/smart) and a play's gather_facts setting (boolean),
which resulted in gathering=explicit being ignored.