Add .await syntax highlighting

[seanmonstar]

Also puts async into its own group in case one wants to highlight it differently.

[rust-highfive]

r? @chris-morgan

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[seanmonstar]

@chris-morgan ping :)

[chris-morgan]

I’m not convinced about requiring (tho not highlighting) the dot, rather than just highlighting await as a keyword. Convoluted code written by madmen that like breaking syntax highlighters:

a .
await
./**/await

Do you have a definite opinion on the presence of the dot in the highlighting, or did that just seem like the thing to do?

[seanmonstar]

I had a small test file when I was writing this, and now I cannot remember why I thought it should start with a .. I'll remove that, for the sake of the madmen.

[seanmonstar]

All set :D

[seanmonstar]

@chris-morgan any other thoughts?

[chris-morgan]

Thanks for the reminder!