Splitted sysconfig into multiple packages

Note: installation-images are adopted in git commit 34f0bdfca4.

- version 0.81.3
- Fixed to reload syslog on hostname changes using systemctl as
there is no /etc/init.d/syslog script since syslog-service-2.0
(bnc#830467).
- Added a systemctl guard to rpm post script
- version 0.81.2
- Added otherproviders(/sbin/ifup) conflict to sysconfig-network.
- Do not stop the network interfaces, but kill the network and all
network@ services to kill all dhcp clients on uninstall.
- version 0.81.1
- Initial network and network@ service files to avoid, that systemd
udevd kills dhcp clients, which where forked from the udev hotplug
rule and for better control (bnc#821879).
- version 0.81.0
- Initial sysconfig split into udevmountd, sysconfig, -netconfig
and -network packages, to allow another implementation of the
/etc/init.d/network and /sbin/ifup scripts.
- Dropped obsolete README files.