Bug 19821: Do not modify KOHA_CONF, use new database_test entry instead

Bug 19821: Do not modify KOHA_CONF, use new database_test entry instead

I have tried to use the original idea of this patch for bug 19185, but
it cannot work as it. ENV is not shared between processus and KOHA_CONF
will not be read by webserver (used for selenium tests).

Moreover on bug 19185 we are testing the installation process and we do
not want the database to be populated with sample data, we just need a
new and clean DB.

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Bouzid Fergani <bouzid.fergani@inlibro.com>
Signed-off-by: Victor Grousset/tuxayo <victor@tuxayo.net>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>