Refactored the zrpc implementation to:

- Most server methods now return data to clients more quickly by writing to
  client sockets immediately, rather than waiting for the asyncore
  select loop to get around to it.

- More clearly define client and server responsibilities. Machinery
  needed for just clients or just servers has been moved to the
  corresponding connection subclasses.

- Degeneralized "flags" argument to many methods. There's just one
  async flag.

src/ZEO/StorageServer.py

@@ -1340,10 +1340,10 @@ class ClientStub:
         self.rpc.callAsyncNoPoll('invalidateTransaction', tid, args)
 
     def serialnos(self, arg):
-        self.rpc.callAsync('serialnos', arg)
+        self.rpc.callAsyncNoPoll('serialnos', arg)
 
     def info(self, arg):
-        self.rpc.callAsync('info', arg)
+        self.rpc.callAsyncNoPoll('info', arg)
 
     def storeBlob(self, oid, serial, blobfilename):
 

src/ZEO/tests/servertesting.py

@@ -56,3 +56,5 @@ class Connection:
 
     def callAsync(self, meth, *args):
         print self.name, 'callAsync', meth, repr(args)
+
+    callAsyncNoPoll = callAsync

src/ZEO/tests/testZEO2.py

@@ -78,9 +78,10 @@ will conflict. It will be blocked at the vote call.
     >>> zs2.storeBlobEnd(oid, serial, data, '1')
     >>> delay = zs2.vote('1')
 
-    >>> def send_reply(id, reply):
-    ...     print 'reply', id, reply
-    >>> delay.set_sender(1, send_reply, None)
+    >>> class Sender:
+    ...     def send_reply(self, id, reply):
+    ...         print 'reply', id, reply
+    >>> delay.set_sender(1, Sender())
 
     >>> logger = logging.getLogger('ZEO')
     >>> handler = logging.StreamHandler(sys.stdout)