v1.4.0

• Added the connection_handler install option. Default value is
  manhole.handle_connection_repl, and alternate
  manhole.handle_connection_exec is provided (very simple: no output
  redirection, no stacktrace dumping).
• Dropped Python 3.2 from the test grid. It may work but it's a huge
  pain to support (pip/pytest don't support it anymore).
• Added Python 3.5 and 3.6 in the test grid.
• Fixed issues with piping to manhole-cli. Now
  echo foobar | manhole-cli will wait 1 second for output from
  manhole (you can customize this with the --timeout option).
• Fixed issues with newer PyPy (caused by gevent/eventlet socket
  unwrapping).