In the code, test, and docs, because it makes it much easier to find
things.

Other than adding the comments about alphabetical order, this commit
only moves things around.

Remove unused rustc_serialize::hex module

* Remove unused `rustc_serialize::hex` module
* Cleanup `Cargo.toml`

…laumeGomez

Moving all rustdoc-ui tests to check-pass

These were all build-pass before and don't seem to need it.

Helps with rust-lang#62277

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Use assoc int consts3

Define module level int consts with associated constants instead of `min_value()` and `max_value()`. So the code become consistent with what the docs recommend etc. Seems natural.

Also remove the last usages of the int module constants from this repo (except src/test/ directory which I have still not really done anything in). Some places were missed in the previous PRs because the code uses `crate::<IntTy>` to reach the constants.

This is a continuation of rust-lang#70857

r? @dtolnay

…ions, r=Dylan-DPC

Alphabetize `-C` and `-Z` options

Because it will make it much easier to find options that way.

r? @petrochenkov