Implement `From<Vec<T>>` and `Into<Vec<T>>` for `VecDeque<T>`

[apasel422]

This can be done without allocating or going through an iterator.

[davidhewitt]

Hi, I've just had a go at implementing this (my first contribution to Rust!). It's in my fork davidhewitt@4a21983

Does this patch look like what you were looking for? If so, I'll open a pull request. Is there anything I should know about opening PRs for Rust (what to name them, do I need to put in a specially formatted description for a bot to parse etc.)?

[apasel422]

@davidhewitt Nice! That is what I was looking for. If you open a PR, I'll leave comments there. The PR title can be the same as your commit message, and the body can contain "Closes #32848" so that this issue can be closed automatically once the PR is merged.

[davidhewitt]

Thanks - #32866!