Move to BenchmarkCI?

[timholy]

JuliaImages/ImageFiltering.jl#150 reorganized the benchmarks for ImageFiltering into a form that would run on each PR and report results separately from tests. To me this seems more useful than the strategy currently used here, where the benchmarks run but failures are reported as warnings. We could consider switching to BenchmarkCI.

[johnnychen94]

There're still some issues to be fixed before the wide usage of BenchmarkCI, e.g, PRs from other forks don't trigger that, CI script doesn't get auto-updates. I prefer to fix them upstream first, and then apply to JuliaImages.

[johnnychen94]

The current benchmark script seems to only benchmark getindex and setindex for channelview and colorview. What's other things you have in mind that definitely worth a benchmark?

[timholy]

Those alone are quite good, and already highlight areas that need fixing (ReinterpretArray has been a bit of a problem child). Perhaps we can add the various functions in src/map.jl. That may be about it, though.