Merge pull request #2104 from robparrott/devel

add_host changes to allow vars
Allow add_host to add hosts to multiple groups, groups is now an alias for groupname.
Added a tunneling example
Added a $PIPE_ONCE lookup plugin, that caches the result so it is only evaluated one time.
Fixup the pipe_once plugin
Avoid the 'state=null' coming back from the service module.
Make note about enablement bit
Make the file module work as expected in check mode
Document new PIPE_ONCE macro
Recurse was added in 1.1
Specified when PIPE_ONCE was added.

Also, now shows when "Getting values from files" was added, a sphinx
directive was missing a colon.
Merge pull request #2109 from lorin/pipe_once_docs

Document new PIPE_ONCE macro
resolve merge conflict
Working on complex argument support.
Remove debug print message
Add complex arguments example
Correct documentation example, Snowball was a hampster.
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.
Flatten argument to with_items

Fixes #1711.
Teach the user module to understand check mode.