Update known issues for Dashing (ros2#260)

* Dashing known issues.

source/Releases/Release-Dashing-Diademata.rst

@@ -762,7 +762,10 @@ rviz
 Known Issues
 ------------
 
-None yet.
+* `[ros2/rclcpp#715] <https://github.com/ros2/rclcpp/issues/715>`_ There is an inconsistency in the way that parameter YAML files are loaded between standalone ROS 2 nodes and composed ROS 2 nodes.
+ Currently available workarounds are noted in an `issue comment <https://github.com/ros2/rclcpp/issues/715#issuecomment-497392626>`_
+* `[ros2/rclpy#360] <https://github.com/ros2/rclpy/issues/360>`_ rclpy nodes ignore ``ctrl-c`` when using OpenSplice on Windows.
+* `[ros2/rosidl_typesupport_opensplice#30] <https://github.com/ros2/rosidl_typesupport_opensplice/issues/30>`_ There is a bug preventing nesting a message inside of a service or action definition with the same name when using OpenSplice.
 
 
 Timeline before the release