Fixes Augeas to Properly Configure Sysctl

The following puppet agent error was observed on nodes:

/Stage[main]/Openshift_origin::Node/Augeas[Tune Sysctl knobs]:
Could not evaluate: missing string argument 2 for set

This prevented Augeas from configuring the necessary sysctl
parameters.
Fix nsupdate plugin config bind key name

This fixes the nsupdate plugin config to work when bind key is not
the same as the domain name.

This was driving me crazy trying to work out why dynamic updates
weren't working when used with an existing DNS infrastructure.
Reenable LDAP auth plugin

LDAP seems to have been broken for a while as the manifest wasn't
even included.
This reenables the plugin, requires the installation of mod_ldap, and
allows specifying credentials to bind to non anonymous access LDAP
directories.
merge in fix brances ldap_plugin, nsupdate_key_name
Merge branch 'sysctl_fix' of https://github.com/danehans/puppet-openshift_origin