Fixes#493
This PR updates the documentation for Browsertrix Crawler 1.0.0 and
moves it from the project README to an MKDocs site.
Initial docs site set to https://crawler.docs.browsertrix.com/
Many thanks to @Shrinks99 for help setting this up!
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Co-authored-by: Henry Wilkinson <henry@wilkinson.graphics>
Co-authored-by: Ilya Kreymer <ikreymer@gmail.com>
