Benchmark iteration test for binary 64 bit timer entries

[michaelplaing]

Show iteration times for various instances of a simple model of timers similar to those used by Redis.

This is the first of 2 PRs. The 2nd PR has changes to iteration for which these new benchmarks provide useful comparisons.

[jcorporation]

I merged your patch in my rax fork that already merged patches from redis.

Test does not compile and is fixed with https://github.com/jcorporation/rax/commit/f089a12f45bfd084ccb83138e0794d3a728aa8c7.

[michaelplaing]

Sigh. Your fix doesn't work on my M1 Mac... I'll look at alternatives.

[jcorporation]

Just merged your fix and it works!