Implement div_euclid / rem_euclid for vec types

[SpecificProtagonist]

Rust's float and signed integer types implement euclidian division via the div_euclid / rem_euclid methods, but this is missing from glam's vec types (in my case, I need it to divide an area into equally sized chunks).

Edit: made a non-vectorized implementation in #419

[SpecificProtagonist]

Looks like this came up in #218, but only div / rem were implemented. I'm a bit confused about the comment, as Rust's div_euclid / rem_euclid were stabilized in before that issue was opened.

[bitshifter]

That was the stabilization commit, those methods didn't make it into a stable Rust release until 1.38.0 in September 2019 https://releases.rs/docs/1.38.0/

[SpecificProtagonist]

Yeah, but that's still a much older Rust version than the MSRV at the time (shrug, doesn't matter now).

[bitshifter]

Hmm, yeah I'm not sure why I didn't think they weren't stabilized in 2021, other than the methods appear to have been renamed since the RFC that Alice linked so maybe I didn't find them in the docs or something.

[bitshifter]

These have been added now.