Make headers in KDoc smaller

[koperagen]

Now at least some of kdocs use h2 header. It's way too big compared to other text. I suggest to make it h4 / use bold

[AndreiKingsley]

Let's remove them at all, at least for operations!

[zaleslaw]

Give me an example?

[Jolanrensen]

@zaleslaw

dataframe/core/generated-sources/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/all.kt

Line 184 in 74c696c

/**

[AndreiKingsley]

No we have a rule.
Have a header only in KDoc-topics, but not in KDoc-snippets.
https://github.com/Kotlin/dataframe/blob/master/KDOC_GUIDELINES.md

[AndreiKingsley]

So now it's a part of a more global issue — bring existing KDocs into compliance with the guidelines