This update fixes the following issue for syslogd and rsyslog:
- syslog-service: Added SYSLOG_REQUIRES_NETWORK variable allowing
the user to configure (override) whether the syslog daemon config
requires network or can be started early. Default is to detect
it for syslogd and syslog-ng and to just start rsyslogd early
with its normal config. Removed the rsyslog.early.conf use as it
is usually not needed [enable on-disk queues] (bnc#728565).

- Cleaned up the config files a bit, updated comments in config
file, marked the /etc/rsyslog.early.conf obsolete.
Note: rsyslog will be started early/before network using its normal
/etc/rsyslog.conf config file (adopted scripts in syslog-service
package). When any kind of remote logging is in use, then on-disk
queues should be enabled. To start it after the network, please set
the SYSLOG_REQUIRES_NETWORK=yes variable in /etc/sysconfig/syslog
(bnc#728565).