docs(blog): 1.15 release

[ikatyang]

There're 50+ items in this release, it'd be appreciated if somebody could pick some of them up.

Feel free to edit this PR directly.

🌟 Live preview 🌟

[j-f1]

I’ll help write some descriptions. A few comments:

[j-f1]

I wonder if these should be formatted differently (grammar-wise)? Perhaps:

First available in vX.X.X. Deprecated in vY.Y.Y

[ikatyang]

Since there's a +, I guess it should be fine?

[lipis]

https://github.com/ikatyang/prettier/pull/2/files

[ikatyang]

You can edit this PR directly, I've checked Allow edits from maintainers..

[lipis]

Thanks @ikatyang.. I was experimenting.. :)

[lipis]

Maybe grouping the languages? https://github.com/prettier/prettier/blob/b944ad58eed30d0dc7abc347e744dbfbe919891d/README.md#opinionated-code-formatter

[lipis]

Beautiful :) But I guess we should merge this after the release.

[ikatyang]

Sure. In the last release, I merged the blog post before the release, which results in no new version available on npm for 12 min. 😂

[lipis]

It looks like we will have to add this one as well: #5327 :)

[suchipi]

I went through and revised wording here and there.

Thanks for driving this release and everything for the last few months, @ikatyang and everyone!

[lydell]

@lipis It might be better to hold off on that PR to the next release.

[lipis]

@lydell Just comment on the original issue.. we didn't add the 1.15 milestone to it anyway.

[existentialism]

Fixed a few small typos, but awesome work!