Show code and reason for non-1000 close events from server

[dstillman]

Currently, if the server closes the connection with an error code, the code and reason aren't shown in the console:

> foo
disconnected

This patch adds them to the "disconnected" line:

> foo
disconnected with error 4400: Error parsing JSON

[jnordberg]

:+1:

[oyvindwe]

+1

[nwwells]

This looks good. Can you resolve the conflicts and then I'll merge?