Reword slf4j references in README

[sschuberth]

The README refers to slf4j in several places, which reads as if kotlin-logging would work for the the JVM target only. But to my understanding Kotlin multi-platform support has been added some time ago. So it should be made more clear in the README that more targets than JVM are supported.

[github-actions]

Thank you for reporting an issue. See the wiki for documentation and slack for questions.

[oshai]

the wiki has this section: https://github.com/MicroUtils/kotlin-logging/wiki/Multiplatform-support

We can add a link to it on the readme.

[sschuberth]

We can add a link to it on the readme.

Thanks for the offer, but my main point is not about adding more information, but removing outdated / wrong information. Having that link in addition to the slf4j references would be even more confusing, IMO.

[oshai]

Would you like to create a pr with the suggestion?

[sschuberth]

While the changes are probably not many lines of code, I'm quite uncertain which parts of the docs are still wanted to refer to slf4j (e.g. for historical reasons), and which not, so I'd rather leave this to someone familiar with the project.

[oshai]

Created PR #255 for it.

[sschuberth]

Created PR #255 for it.

Thank you!