Add benchmarks

Branched off of https://github.com/dedupeio/dedupe/issues/965#issuecomment-1046319666.

EDIT: See next comment for using ASV instead of @profile

Place @profile decorators on bottleneck functions using memory_profiler

List this dependency as extra, so that most users don’t need to install it.

Also, to prevent overhead from @profile getting run always (even when we don’t want profiling), wrap it in our own custom decorator that is usually a noop:

def dd_profile(func, *args, **kwargs):
    # Maybe a better way to configure this? Would have to be at import time
    if os.environ["DEDUPE_PROFILE"]:
        # Actually add the profiler wrapper
        return profile(func, *args, **kwargs)
    else:
        # noop
        return func

Next steps are to probably actually make a new branch and apply it to some of the examples?

[fgregg]

i think precision and recall are really still the best ones.

[fgregg]

look at canonical.py in tests to see how precision and recall is calculated there.