message: Add id to start guide so we can simplify tests in the future.
diff: @@ -32,7 +32,7 @@ export class StartGuide extends SafetyFirst {
  return null;
  }
  /* eslint-disable react/jsx-no-target-blank */
  - return <div className="co-well">
  + return <div className="co-well" id="tectonic-start-guide">
  {this.state.dismissible && <button className="btn btn-link pull-right" onClick={() => this.dismiss()}>Dismiss</button>}
  <h3 style={{marginBottom: 20}}>Tectonic Quick Start Guide</h3>
  