Type detection based on SysFs.

In fact type detection from netconfig is reused instead of parsing
sysfs and reimplementing it.
Integrated GetTypeFromSysfs into common type detection workflow.

Conflicts:
	library/network/src/NetworkInterfaces.ycp
Adapted testsuite.

Supresses an output generated by shell execution in GetTypeFromSysfs
Newly imported FileUtils emits more log messages as well.
Updated changelog.