MB-3162 - early closing code in conn_new() fixed
MB-3162 - early closing code in conn_new() fixed

The previous change to reject client conns exposed an old bug in
conn_new(), where libevent'ed conns were incorrectly added to the conn
freelist.

This fix clears up the libevent registration and avoids the freelist
when moxi rejects a client conn early.

Change-Id: I6e13271f10a8268e14ebf3de210026c23128a3b8
Reviewed-on: http://review.membase.org/4058
Tested-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>
Reviewed-by: Chiyoung Seo <8b279095f11c26cc21045fda5a3e51debb005aa9@gmail.com>

membase/moxi,membase/moxi,couchbase/moxi,zbase/moxi,membase/moxi,couchbase/moxi,zbase/moxi,couchbase/moxi,membase/moxi,membase/moxi,zbase/moxi,couchbase/moxi,zbase/moxi,zbase/moxi,membase/moxi,couchbase/moxi,couchbase/moxi