Bug 18562: Add manpage for koha-sip

Bug 18562: Add manpage for koha-sip

This patch adds the manpage for koha-sip.

To test:
- Apply this patch
- Run:
  $ kshell
 k$ prove xt/verify-debian-docbook.t
=> SUCCESS: Tests pass!
- Run:
  $ misc4dev/cp_debian_files.pl
  $ man koha-sip
=> SUCCESS: The man page shows correctly.
- Sign off :-D

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>