Tracking issue for Rename int/uint to isize/usize (RFC 544)

[aturon]

rust-lang/rfcs#544

Specifically, int and uint should be deprecated in favor of isize and usize.

[aturon]

cc @cmr @CloudiDust

[pnkfelix]

( @huonw has a branch with much of this implemented: https://github.com/huonw/rust/tree/int-feature ; I am currently trying to shepherd that branch into a landable state )

[steveklabnik]

What actually closes this issue, is it when int/uint is totally gone?

[nagisa]

We have another issue to audit our uses of int/uint in (at least in parts of) the code base. #22240

[aturon]

@steveklabnik I this we can declare this issue as done; as @nagisa, we're tracking the audit/API renaming elsewhere.