Add app_queue_size Python property.

prrt/prrt.pyx

@@ -96,6 +96,19 @@ cdef class PrrtSocket:
                 raise Exception("Not a sender.")
             cprrt.PrrtSocket_set_sock_opt(self._c_socket, "targetdelay", value)
 
+    property app_queue_size:
+
+        def __get__(self):
+            if not self.isSender:
+                raise Exception("Not a sender.")
+            return cprrt.PrrtSocket_get_sock_opt(self._c_socket, "app_queue_size")
+
+        def __set__(self, value):
+            if not self.isSender:
+                raise Exception("Not a sender.")
+            cprrt.PrrtSocket_set_sock_opt(self._c_socket, "app_queue_size", value)
+
+
     def recv(self):
         cdef char buffer[65536]
         cdef int32_t len