Bug 10617 - koha-common init script cleanup

Bug 10617 - koha-common init script cleanup

Removed unused stuff, added a new config file /etc/default/koha-common
to control the init script behaviour. Currently is only a stub. The config
file could be put on /etc/sysconfig on RedHat and friends. The init script
should work them too. Added a TODO comment regarding the 'status' switch.

To test:
- Apply the patch on master, build your own packages and install.
- The init script should continue to work as expected.
(it can be tested replacing the /etc/init.d/koha-common file with
debian/koha-common.init on a packages install).
- The absence of the /etc/default/koha-common file should not prevent
the init script from working.

Sponsored-by: Universidad Nacional de Cordoba
Signed-off-by: Robin Sheat <robin@catalyst.net.nz>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>