Update criterion requirement from 0.5.1 to 0.6.0

Updates the requirements on [criterion](https://github.com/bheisler/criterion.rs) to permit the latest version.
- [Changelog](https://github.com/bheisler/criterion.rs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/bheisler/criterion.rs/compare/0.5.1...0.6.0)

---
updated-dependencies:
- dependency-name: criterion
dependency-version: 0.6.0
dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Update rand dep

Update rustc-hash requirement from 1.1.0 to 2.1.1

Updates the requirements on [rustc-hash](https://github.com/rust-lang/rustc-hash) to permit the latest version.
- [Changelog](https://github.com/rust-lang/rustc-hash/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rust-lang/rustc-hash/compare/v1.2.0...v2.1.1)

---
updated-dependencies:
- dependency-name: rustc-hash
dependency-version: 2.1.1
dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Release version 1.0

Add iterator compat

Add builder function

Add testing ci

Update version, edition, and MSRV

Switch to a treap

Note differences from far more thorough implementation at https://github.com/apanda/cvm

It's not a real test, just allows quick calculation of the actual count

Count anything that impls PartialOrd and PartialEQ

It doesn't duplicate, it re-orders elements.