Callback Plugin Context / Naming Fixes

PKGBUILD update

Doc update

This lets packages use ansible-git as a dependency in place of ansible.

makepkg will automatically compress man pages in MAN_DIRS if 'zipman'
is in the OPTIONS array of makepkg.conf.

Ansible has modules for package managers other than yum and apt,
so update the documentation accordingly.

Link to the Inventory & Patterns page in places where the Getting
Started guide refer to it, so that users unfamiliar with the
inventory syntax can easily familiarize themselves with it.

show entire doc index in left sidebar on the documentation home page

Renamed on_no_hosts_matched/on_no_hosts_remaining to correct names in noop callback, added methods to callback plugin examples.

Updates to the authorized_key documentation

Add rhnreg_ks module

Simple zypper module to install, remove, or upgrades packages.

* Clarified the meaning of 'user'
* Changed 'sshdir' to 'path' in the example
  * 'sshdir' is used internally in the module, but the argument is 'path'
* Made the capitalization consistent in the descriptions

Also ...
 * When unregistering, first unsubscribe from all content

rhnreg_ks command allows users to manage registration to a Red Hat
Network (RHN) (e.g. rhn.redhat.com) server.  The moduel will also
interact with the specified RHN system via XMLRPC as needed.

Before proceeding with registration, the rhnreg_ks module will enable
the system to receive updates from RHN.  This involves enabling the
appropriate RHN yum plugin, as well as disabling an active
subscription-manager yum plugin.

Once enabled, the module will support the following operations:
 * configure
 * register
 * subscribe to custom child channels (see `rhn-channel` command)
 * unregister

Update changelog

The subscription_manager module acts as a wrapper to the command
'subscription-manager'.  The subscription-manager utility allows users
to manage RHN registration, subscription and yum repositories from the
Red Hat Entitlement platform.

Currently, this module supports the following sub-commands:
 * config
 * [un]register
 * subscribe

lineinfile example: /etc/host[s]