Create NonZero trait with primitive associated type

[nvzqz]

This enables getting the primitive integer type for a nonzero type through a type alias.

r? @yaahc

[nvzqz]

I'm open to suggestions for a better name.

[rust-log-analyzer]

The job x86_64-gnu-llvm-12 failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

---- src/num/nonzero.rs - num::nonzero::NonZero::Scalar (line 27) stdout ----
error[E0432]: unresolved import `std::num::NonZero`
 --> src/num/nonzero.rs:28:16
  |
4 | use std::num::{NonZero, NonZeroU32};
  |                |
  |                |
  |                no `NonZero` in `num`
  |                help: a similar name exists in the module: `NonZeroI8`
error: aborting due to previous error

For more information about this error, try `rustc --explain E0432`.
Couldn't compile the test.

[yaahc]

Hey @nvzqz, can you add more detail to the top level comment explaining how you plan to use this API? I'm a little confused by the description you gave, is the NonZero type the one being aliased or are you creating an alias using the type exposed via this trait? Ideally I'd love to see a link to a branch on a crate where you intend to use this API testing out the API and demonstrating the intended usage.

[yaahc]

@rustbot label: -S-waiting-on-review +S-waiting-on-author

[JohnCSimon]

@nvzqz
Ping from triage: I'm closing this due to inactivity, Please reopen when you are ready to continue with this.
Note: if you do please open the PR BEFORE you force push to it, else you won't be able to reopen.
Thanks for your contribution.

@rustbot label: +S-inactive