Moar tests

fix up formatting for code sections in guide_aws

They're not being run by default so make sure they're ready to show
errors when we turn them on for v2

(and a few unicode tests because they make clearer what we're testing)
works.  disabled for now since they mostly do not pass on 1.8.  We'll
want to enable them when we start integration testing the v2 tree.

Typo fix in playbook delegation docs.

Typo fix

Fixes #9758

Add missing connection and header

Docfix: checking a background task

Minor changes to wording on how to check a background task with async_status.

Fixes #9740

Docfix: running background tasks without polling

typofixes - https://github.com/vlajos/misspell_fixer

Disable automatic running of test_delegate_to with an explanation of what it would take to set this up in our automated test systems

Fix the example in the doc to explicitly set the poll interval to zero so the
job doesn't poll.

To run a background task without polling, you need to set the poll interval to
zero. However, Ansible's default poll setting is 15 seconds, so not specifying the poll
interval will cause a background job to poll.

Have known_hosts function use the url parameter instead of getting a specific attribute out of the module dict.

This makes the function useful in more places