title: Joining React props with custom props
body: <p>When defining props in React, using Typescript, it seems that the default React props get overwritten by whatever the interface is. Is there a clean way to merge the two without having to specify every prop React already knows about?</p>
  
  <p>Example:</p>
  
  <pre><code>interface IProps { // extends React.???
     title: string;
     // Generally seen adding children?: any
     // But this can get out of hand with onClick, onChange, etc
  }
  
  function MyComponent(props: IProps) {
     return props.children; // Typescript error: children doesn't exist on props
  }
  </code></pre>