add Default-Start & Default-Stop to LSB header

Add an empty Default-Start and Default-Stop line to the LSB Header
in order to prevent chkconfig on openSUSE from complaining:

  # chkconfig munge on
  insserv: Script munge is broken: incomplete LSB comment.
  insserv: missing `Default-Start:'  entry: please add even if empty.
  insserv: exiting now!
  /sbin/insserv failed, exit code 1

Installing RPMs for munge-0.5.10 on openSUSE (12.2, 12.1, 11.4)
generates the following warnings:

  # rpm -ivh munge-0.5.10-1.x86_64.rpm munge-libs-0.5.10-1.x86_64.rpm
  insserv: script munge is broken: incomplete LSB comment.
  insserv: missing `Default-Start:'  entry: please add even if empty.
  insserv: script munge is broken: incomplete LSB comment.
  insserv: missing `Default-Start:'  entry: please add even if empty.
  insserv: Default-Start undefined, assuming default start runlevel(s)
           for script `munge'

In regards to these missing LSB Header entries, both the Fedora and
openSUSE packaging guides state:

  https://fedoraproject.org/wiki/Packaging:SysVInitScript
  http://en.opensuse.org/openSUSE:Packaging_init_scripts

  Only services which are really required for a vital system should
  define runlevels here. If the service does not start by default in
  any runlevel, this line should be omitted.

But omitting these lines causes chkconfig on openSUSE to complain.
Adding lines for Default-Start and Default-Stop silences these
warnings.

Both of these entries are empty (ie, no runlevels are specified)
since MUNGE is not started by default in any runlevel.  This behavior
matches the chkconfig line as required.

While the missing entries did not cause problems on Fedora or Red Hat,
adding empty entries did not create any problems.

Tested on:
- Fedora 17
- openSUSE 12.2, 12.1, 11.4
- RHEL 6, 5

Fixes issue 9.

src/etc/munge.init.in

@@ -15,6 +15,8 @@
 # Should-Start:       $named $syslog
 # Should-Stop:        $named $syslog
 # Short-Description:  Start/Stop the MUNGE authentication service.
+# Default-Start:
+# Default-Stop:
 # Description:        MUNGE (MUNGE Uid 'N' Gid Emporium) is a highly scalable
 #                     authentication service for creating and validating
 #                     credentials.