* Fix the task_vars parameter to not default to a mutable type (dict)
* Implement invocation in the base class's run() method have each action
module call the run() method's implemention in the base class.
* Return values from the action plugins' run() method takes the return
value from the base class run() method into account so that invocation
makes its way to the output.
Fixes#12869
This adds a parse_address(pattern) utility function that returns
(host,port), and uses it wherever where we accept IPv4 and IPv6
addresses and hostnames (or host patterns): the inventory parser
the the add_host action plugin.
It also introduces a more extensive set of unit tests that supersedes
the old add_host unit tests (which didn't actually test add_host, but
only the parsing function).
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
Toshio Kuratomi
Abhijit Menon-Sen
Ryan Petrello
James Cammarata