proof 0.2.0

Features

• #18: The version snippet, so reports and the compatibility matrix show which version of a server proof checked.
• #18: proof matrix -html, which builds the compatibility matrix as a web page, and the daily matrix of the bundled profiles on GitHub Pages.
• #19: Profiles for nbb and let-go, and scenarios for proof serve that act like them.
• #20: Client profiles for clojure-cli.repl and bb repl --connect.