title: @storybook/addon-controls: howto not auto-generate control for a certain prop
body: <p><code>@storybook/addon-controls</code> is fun, however I cannot find a way to disable control generation for a given arg. Lets say I have a component prop that is an event handler and I obviously do not want it to have a control. So I want it to appear in the list of props with the name, type and description, but no control. How do I do that?</p>