Bug 17467: Add koha-zebra script to handle Zebra daemons

Bug 17467: Add koha-zebra script to handle Zebra daemons

This script is intended to replace the following currently used scripts
on packages setups:
- koha-start-zebra
- koha-stop-zebra
- koha-restart-zebra

It also introduces a --status option switch, for asking for daemon statuses

To test

- Apply the patch
- Run:
  $ sudo debian/scripts/koha-zebra --start kohadev
=> SUCCESS: same behaviour than koha-start-zebra kohadev
- Run:
  $ sudo debian/scripts/koha-zebra --stop kohadev
=> SUCCESS: same behaviour as koha-stop-zebra kohadev
- Run:
  $ sudo debian/scripts/koha-zebra --restart kohadev
=> SUCCESS: same behaviour than koha-restart-zebra kohadev
- Run:
  $ sudo debian/scripts/koha-zebra --status kohadev
=> SUCCESS: It correctly shows the status for the running (or not) process

Play with different combinations of this commands

Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>