Add simple chat based on EventMachine with Couchbase logger

Change-Id: If0a80f31d87ba632ff6510e2175c340dfcc876ba
Reviewed-on: http://review.couchbase.org/24480
Tested-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>