Applying callback model to runner, and using that in playbooks, so output can be more immediate in playbooks.

(Runner still does not use callbacks for default output)

refactoring of playbooks now warranted, which we'll do before we move on.   This variable assignment
system makes nearly all possible magic possible, for we can use these variables however we like,
even as module names!

Playbook test upgrades, made some notes about callbacks we need to add.  Still need to compare events
recieved vs expected so we can be notified if this test breaks, and also to add some more detailed
playbooks that use includes & async, etc.