nagiosgen: Fix icon for the unifi group

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
nagiosgen: Update icons

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
nagiosgen: Add ubuntu-12.04 group

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
nagiosgen: Add printer group and tests

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>