Add more int type aliases

[AndrolGenhald]

Oh, I thought I already added negative-int but I guess not. It should be easy to do if someone wants to add that

Originally posted by @orklah in #8060 (comment)

Should be trivial to add in Atomic::create (see how positive-int is handled there).

We'll probably want

• non-negative-int
• negative-int
• non-positive-int

just for completeness sake.

[orklah]

Note to my future self: I need to think of pinging Ondrej on that if new keywords are implemented

[weirdan]

I don't think we need those now that we have integer ranges:

• non-negative-int = int<0, max>
• negative-int = int<min,-1>
• non-positive-int = int<min, 0>