Add http response code to example - fixes safari

[anotherjesse]

Safari/iOS web clients will fail if the the HTTP response code isn't sent

Safari shows an error:

Safari Can't Open The Page
Safari can't open the page "10.0.0.75" because the server unexpected dropped the
connection. This sometimes occurs when the server is busy. Wait for a few minutes,
and then try again

By adding the http response code safari, chrome, firefox all will render the webpage

[anotherjesse]

Looks like links/lynx web browsers need to have a Content-Type header as well:

    cl.send('HTTP/1.0 200 OK\r\nContent-type: text/html\r\n\r\n')