0.19.2

Changed

• Commands are written to the websocket by a writer thread. A command waiting behind a large one the browser is slow
  to take fails after its own timeout: instead of the large one's, and the connection is closed only after the
  browser takes no data for protocol_timeout, so a shorter pause no longer kills it [#676]

Fixed

• On JRuby Ferrum::Browser.new hung forever in the websocket handshake: the nonblocking write from [#644] waits for
  the lock JRuby holds while the reader thread is blocked reading the same socket. Writes are blocking again [#676]