zfs: documentation no longer breaks the formatting in webdocs

Fixing syntax error

running install_lib
byte-compiling /usr/lib/python2.6/site-packages/ansible/runner/action_plugins/add_host.py to add_host.pyc
SyntaxError: ('invalid syntax', ('/usr/lib/python2.6/site-packages/ansible/runner/action_plugins/add_host.py', 37, 92, '    def run(self, conn, tmp, module_name, module_args, inject, complex_args=None, **kwargs)\n'))

Fixes #1711.

We all agreed on the list that the ansible module common module snippet, since it's dynamically embedded in modules on the fly, should
be a BSD licensed snippet so that it's ok to write proprietary modules.  The actual license of Ansible (GPLv3) or any modules
written for ansible (any) do not change.

Document new PIPE_ONCE macro

Also, now shows when "Getting values from files" was added, a sphinx
directive was missing a colon.

add_host changes to allow vars

add the ability to take variables in the add_host module, and be willing to parse a host:port hostname handed to add_host

Hate to do this, but URI module docs were constructing messed up RST files, so removing examples for now.  Will ask someone to work on them.

Rough cut at adding a glossary section.  This could definitely use some improvements, proof reading, and lots of cross linking.