get redis host/port from connection_pool object instead of main object

redis-py 2.4.0 removed host/port accessors on the main Redis object.
If those accessors aren't available, get a connection object from the
connection_pool and get the host/port from there.  Store the host
and port on the ResQ object so we don't have to keep poking the
connection pool.

pyres/__init__.py

@@ -141,8 +141,17 @@ def _set_redis(self, server):
             self.dsn = server
             host, port = server.split(':')
             self._redis = Redis(host=host, port=int(port))
+            self.host = host
+            self.port = int(port)
         elif isinstance(server, Redis):
-            self.dsn = '%s:%s' % (server.host,server.port)
+            if hasattr(server, "host"):
+                self.host = server.host
+                self.port = server.port
+            else:
+                connection = server.connection_pool.get_connection()
+                self.host = connection.host
+                self.port = connection.port
+            self.dsn = '%s:%s' % (self.host, self.port)
             self._redis = server
         else:
             raise Exception("I don't know what to do with %s" % str(server))
@@ -194,7 +203,7 @@ def info(self):
             'workers'   : len(self.workers()),
             #'working'   : len(self.working()),
             'failed'    : Stat('failed',self).get(),
-            'servers'   : ['%s:%s' % (self.redis.host, self.redis.port)]
+            'servers'   : ['%s:%s' % (self.host, self.port)]
         }
 
     def keys(self):

resweb/views.py

@@ -20,7 +20,7 @@ def close(self):
         self.resq.close()
 
     def address(self):
-        return '%s:%s' % (self.resq.redis.host,self.resq.redis.port)
+        return '%s:%s' % (self.resq.host,self.resq.port)
 
     def version(self):
         return str(__version__)
@@ -263,7 +263,7 @@ def title(self):
         if self.key_id == 'resque':
             return 'Pyres'
         elif self.key_id == 'redis':
-            return '%s:%s' % (self.resq.redis.host,self.resq.redis.port)
+            return '%s:%s' % (self.resq.host,self.resq.port)
         elif self.key_id == 'keys':
             return 'Keys owned by Pyres'
         else: