on_skipped callback being passed an extra item parameter that it wasn't
expecting.
Fixed it so that on_skipped in TestCallbacks accepts and ignores the
extra parameter
Extra parameter was added in 4b9b9a8a
but not really clear why from commit message

Remove the -D module debug flag, which no longer is functional due to sudo pty requirements, and replace with -v/--verbose.

This flag will show playbook output from non-failing commands.  -v is also added to /usr/bin/ansible, but not  yet used.

I also gutted some internals code dealing with 'invocations' which allowed the callback to know what module invoked
it.  This is not something 0.5 does or needed, so callbacks have been simplified.

In playbooks, hosts can be a YAML list. We templated the list before
converting it to a semicolon-separated string, which actually templated its
repr. This converts to a string first. A basic unit test is included.

Do not run unit tests against the EVENTS code because it is subject to change and that does not mean anything is broken.
If we want to test playbooks, it's best to test the result of a playbook to make sure it does the correct thing.  Also
remove playbook2/3 yml which were not used.

There's not need to run the complete include through the templating engine.
Several variables were not included before the conditional was evaluated.

ansible-playbook release-my-app.yml --extra-vars="version=123"

And make $version available in the playbook without re-editing the file

Simplify playbook tests so things are not timing dependent in the poll section, which is leading to tests
not being consistent between runs, even though there wasn't an error.  Now we'll just check the final change
counts, which should be just as solid and lead to less churn in the events file.

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.