This changeset addresses the issue reported here:
ansible/ansible-modules-core#1765
The yum module (at least) includes its task results as strings, rather than
dicts, and the code this changeset replaces assumed that in that instance the
task was skipped. The updated behaviour assumes that the task has been
skipped only if:
* results exist, and
* all results are dicts that include a truthy skipped value
* fixed a bug in which failures from a with_* loop were not being
caught correctly, leading to tasks continuing when they should stop
* when ignore_errors is enabled, the failure will no longer count
towards the number of failed tasks