We now disconnect ourselves if we don't get the server's response to a
keepalive request within 30s. This way we will eventually disconnect if
the network goes away but the socket is not closed.*
* See code.google.com/p/chromium/issues/detail?id=197841 and
https://stackoverflow.com/questions/11755605/chrome-websocket-connection-not-closed-when-browser-closed
We will then try to reconnect once a minute (See 8a10c96);
Keepalives belong at this level anyway, since the format is defined by
both the websocket resource protocol and our specific server url
structure.
// FREEBIE