unexpected perf results and questions

[sarnold]

Since I need a good re2 python interface (and there appears to be many, largely unmaintained) I ended up testing this one and the google one using your performance.py script and the results are somewhat unexpected compared to the performance table in the README https://github.com/andreasvc/pyre2#performance

I made a small change to make it run with newer python return _wikidata.decode('utf8') which is maybe why the results look odd; can you verify whether this is correct or not?

re2-perf-data.txt