Prefer more Inclusive language - New gem version

[andyatkinson]

I've replaced whitelist and blacklist with allowlist and blocklist

The test suite is passing for m locally with a couple of newer dependencies and on a more recent version of Ruby

I updated the README to reflect the status although I could back that change out

I updated the gemspec with jeweler.

I'm wondering if a newer version of the gem can be released, 1.1. If you'd like, I'm happy to perform the release, although I'd need to be added to the gem owners: https://guides.rubygems.org/command-reference/#gem-owner

Thank you for this work back then. We're using this in production. I'm in a position to spend a little time on the maintenance of it as well, but initially we'd just like to make these changes. Cheers!