central syslog service, i.e. logsink.stanford.edu.

This change is to allow the v7 rsyslog template to be corrected
without changing the default rsyslog behavior.

* Forward messages to central syslog server
* Change date format

Add an apt preferences file to use the rsyslog version from
backports.  Remove preferences installation from the syslog
module.

Correct variable used to identified the syslog server to send output
to in base::syslog::fragment.

Update comment documentation in base::pam::workgroup.  Remove unused
parameter and variables.

The output templates can be ignored if they are not useful for a
specific configuration.  Most of them time they are useful and
releaves custom configurations from the responsibility of installing
the templates separately when they are needed.

When using v7 add an apt preferences fragment that pulls rsyslog
from backports.

This also leaves a place for redhat folks to add special processing.

This should be overridden for testing syslog sink configurations.

default format that pulls all template and output configuration from
the rsyslog.d fragments directory.  Current default behavior is not
changed for now.

Add v5 and v7 fragments for default templates and output.  New
fragments to support a more complete time format.

Modifying the syslog support to not install /etc/syslog.conf affects
many manifest.  Just ignore it for now.

The original method of overriding the use of /etc/syslog.conf failed
because of a duplicate declaration of the file resource.  This
restructuring should solve that problem.

This change does not affect the current usage of the module.  It does
allow manifests to choose to retire /etc/syslog.conf in favor or
fragments in /etc/rsyslog.d to control the syslog activity.  One
default fragment, 90-local.conf, that writes syslog messages
locally.

This change also include a fragment define that is used for the
management of rsyslog fragments.

* since it's too easy to use a hyphen--which is invalid