Improve output for a few KCMs

I guess it's my first proper KDE contribution attempt, so please don't hate me if I messed something up.

Improve output for Network Interfaces

The implementation is based on what firmware_security is doing to display colorful fwupdmgr output.

The ip command supports colors, so it begs to use them for nicer display. Also included is human-readable transfer statistics, plus network interfaces are separated by an extra newline for ultimate readability.

Before:

After:

Improve output for CPU

The hierarchic output is normally the default when lscpu is invoked from an interactive terminal, but dynamically disabled if the output is piped somewhere. Here we explicitly enable it, so that the output in KInfoCenter is nicer and more readable just as well!

Before:

After:

Improve output for Memory

The --type is changed to "memory", which also includes Physical Memory Array (with also very useful information/summary of memory capabilities on the device).

The option --quiet skips verbose prints about dmidecode (its version and status information). It also skips fairly useless handle address lines. The final output is then much nicer to read.

Before:

After: