Document usage of IP address printing

[razvand]

Add a section in the Networking lab on using specific printing formats for IP address, such as %pI4. Add examples.

[sergiu121]

There is one in the first exercise, but there was a problem in the initial lab commit. I fixed the problem in #129.

[razvand]

There is one in the first exercise, but there was a problem in the initial lab commit. I fixed the problem in #129.

My proposal was to have actual examples and explanation as part of the lab text, not the exercises.

[sergiu121]

Would it be ok to move the explanation to a netfilter subsection?

[razvand]

Would it be ok to move the explanation to a netfilter subsection?

I think it's OK. I would recommend to add a separate section at the end of the lab titled "Printing network addresses". With 2 paragraphs and some small code snippets as usage samples.