polish(v2): improve Docusaurus 1 to 2 migration developer experience

[slorber]

I recently migrated TS cheatsheets from v1 to v2.

Here are migration doc additions, and improved error messages, that would have helped me save some time.

[docusaurus-bot]

Deploy preview for docusaurus-2 ready!

Built with commit 8331763

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[slorber]

Hi @lex111 @yangshun this is ready to review

Apart docs and better error messages, I also made sure that a navbar link with no defined position actually appears in the navbar (right, as v1), as I was surprised to get my items not appearing anywhere ^^

[yangshun]

Apart docs and better error messages, I also made sure that a navbar link with no defined position actually appears in the navbar (right, as v1), as I was surprised to get my items not appearing anywhere ^^

This is my bad. It initially had a fallback, but I removed it to make it explicit. I think I was thinking if we could have 'center' as a valid option in future 😂

[slorber]

I'm not agaist making it explicit actually, as long as we have an error saying the position is missing :)

[yangshun]

Thank you! Let's use the commit message format for easier PR triaging when releasing. I think this would be under "tag: polish" :D

[lex111]

@yangshun FYI we don’t have a commit type as "polish", instead we need to use a "refactor".

[yangshun]

But we have a tag for it. Can we add the polish commit type?

[lex111]

Perhaps it's better (more usual) to replace polish with refactor. https://github.com/facebook/docusaurus/blob/master/lerna.json#L11

[lex111]

Although I still don't see the big trouble here, the types of commits and lerna labels do not have to match. This is a bit confusing, but we don't have many labels 🤷‍♂️