Lp 1933984: Improve OpenSRF::Utils::daemonize

Lp 1933984: Improve OpenSRF::Utils::daemonize

Improve the Perl daemonize function to:

  1. Set the umask to a reasonable, known value (022).

  2. Close all open file descriptors inherited from the parent.

  3. Open /dev/null for standard input, standard output, and standard
  error so that library calls do not clutter the console.

For the logic behind these changes see Chapter 13 of __Advanced
Programming In the UNIX Environment, 3rd Edition__ by W. Richard
Stevens and Stephen A. Rago.

Signed-off-by: Jason Stephenson <jason@sigio.com>