Add Pyro4 transport

Use a Pyro proxy as channel.  Published object must implement methods
used in the Channel class for the shared_queues object. Once published
this object can be shared across multiple hosts.

Sample object backing:
https://github.com/tahmmee/pyroqueue/blob/master/pyroqueues.py

kombu/transport/pyro.py

@@ -0,0 +1,96 @@
+"""
+kombu.transport.pyro
+======================
+
+Pyro transport.
+
+"""
+from __future__ import absolute_import
+
+import Pyro4
+from Pyro4.errors import NamingError
+from Queue import Queue
+
+from . import virtual
+
+DEFAULT_PORT = 9090
+
+class Channel(virtual.Channel):
+
+
+
+    def __init__(self, *args, **kwargs):
+        super(Channel, self).__init__(*args, **kwargs)
+        transport = args[0]
+        self.shared_queues = transport.shared_queues
+
+    def queues(self):
+        return self.shared_queues.get_queue_names()
+
+    def _new_queue(self, queue, **kwargs):
+        if queue not in self.queues():
+            self.shared_queues.new_queue(queue)
+
+    def _get(self, queue, timeout=None):
+        queue = self._queue_for(queue)
+        msg = self.shared_queues._get(queue)
+        return msg
+
+    def _queue_for(self, queue):
+        if queue not in self.queues():
+            self.shared_queues.new_queue(queue)
+        return queue
+
+    def _put(self, queue, message, **kwargs):
+        queue = self._queue_for(queue)
+        self.shared_queues._put(queue, message)
+
+    def _size(self, queue):
+        return self.shared_queues._size(queue)
+
+    def _delete(self, queue, *args):
+        self.shared_queues._delete(queue)
+
+    def _purge(self, queue):
+        return self.shared_queues._purge(queue)
+
+    def after_reply_message_received(self, queue):
+        pass
+
+
+class Transport(virtual.Transport):
+    Channel = Channel
+
+    #: memory backend state is global.
+    state = virtual.BrokerState()
+
+    default_port = DEFAULT_PORT
+
+    driver_type = 'pyro'
+    driver_name = 'pyro'
+
+    def __init__(self, client, **kwargs):
+        super(Transport, self).__init__(client)
+        self.client = client
+        self.default_port = kwargs.get("default_port") or self.default_port
+        self.shared_queues = None 
+
+        conninfo = self.client
+        for name, default_value in self.default_connection_params.items():
+            if not getattr(conninfo, name, None):
+                setattr(conninfo, name, default_value)
+
+        if conninfo.hostname == 'localhost':
+            conninfo.hostname = '127.0.0.1'
+
+        Pyro4.config.HMAC_KEY=conninfo.virtual_host
+        try:
+            nameserver = Pyro4.locateNS(host=conninfo.hostname, port=self.default_port)
+            uri = nameserver.lookup(conninfo.virtual_host) # name of registered pyro object
+            self.shared_queues = Pyro4.Proxy(uri)
+        except NamingError as ex:
+            err = "Unable to locate pyro nameserver (%s) on host %s" % (conninfo.virtual_host, conninfo.hostname)
+            raise NamingError(err)
+
+    def driver_version(self):
+        return 'N/A'