Use a better service example for the factory

Use a real service for the factory.
Add sysvinit service example to factory

There was only an example for systemd but not sysvinit.
Fix Autoyast unit test name

The class name KiwiConfig was used instead of Autoyast.
Extend factory service examples by a disabled service

Extened both service examples (systemd and sysv) to have a disabled
service to improve our tests.
Add enabled?, disabled? methods to service data modell

To abstract the handling of systemd and sysvinit services
the methods enabled? and disabled? were added to the services
data modell.
Implement service support to Autoyast export

We use the deprecated Autoyast services definition because it is
supported by SLES11SP3 and SLES12.
https://github.com/yast/yast-services-manager
Merge pull request #404 from SUSE/extend_autoyast_export2

Extend autoyast export2