tunnel just as it would with HTTPS. For prior knowledge with proxies OkHttp's is now consistent
    with these curl arguments:

    ```
    curl \
      --http2-prior-knowledge \
      --proxy localhost:8888 \
      --proxytunnel \
      http://squareup.com/robots.txt
    ```

 *  Fix: Support executing OkHttp on kotlin-stdlib versions as old as 1.4. The library still builds