Crash report when socket accidentally closes

[tbstenbock]

In the situation where socket connection to RethinkDB server is lost then gen_rethink issues a crash report instead of graceful shutdown. Even when using gen_rethink_session this is happening. The reason for this is the following handle_info statement int he gen_rethink.erl file:

handle_info({tcp_closed, Socket}, State=#{socket := Socket}) ->
{stop, closed, State};

Which should be modified to:

handle_info({tcp_closed, Socket}, State=#{socket := Socket}) ->
{stop, {shutdown, closed}, State};

And with this the crash report is avoided and hence false alarms are avoided.