Migrate logging documentation from swift.org to this repo

[czechboy0]

Migrate logging documentation from swift.org to this repo: https://www.swift.org/documentation/server/guides/libraries/log-levels.html

[natikgadzhi]

Should we put them in the DocC bundle, roughly here? Should we replace the swift.org page with a short paragraph and a link to swift-log docs on SPI?

I haven't looked what links to that page on swift.org yet, hypothetically we could just redirect from it?

Happy to clean this up if you need a pair of hands.

[czechboy0]

Hi @natikgadzhi,

yes exactly - move it into the docc bundle as articles, then we'd shorten the original Swift.org posts just to explain the docs have moved.

We'd appreciate your help!

[FranzBusch]

In addition to that, it would be good if we can move most if not all of the documentation from the readme into the doc bundle. This probably needs some editorial work to come up with a good mix of the documentation from both sources.