* should not need <>, but fails without
* adds anchor to keywords page, uses it on plugins pages
* fixes envvar link errors
* harmonize file name and ref name as python_3
* removes undefined-lable from ignore list
* Fixup keyword dumping
* Clarify introductory text
* Turn links in the keyword description into seealso entries in the rst.
* Have plugin_formatter cleanup trailing whitespace
The indent filter in jinja2 < 2.10 indents blank lines by default which
leads to trailing whitespace. Cleanup after that filter.
* Edits
* Copy edit
* Use a rst glossary for playbooks_keywords docs
* Add a 'Task' and 'Tasks' to glossary.
* Update keywords desciptions,
* use :term: rst ref, some quoting
* Make it more obvious that 'retries' and 'until' need to be used in combination.
