title: How to add custom notes to the toolbox in react echarts
body: <p>I want to add a custom notes on the tool box in react echarts.
  Using below code i am able to add the text box.</p>
  <p>When i click on text box i want to write some text and save it to the load chart. Is there any way to acheive this functionality. Please let me know. Thanks .</p>
  <pre><code>enter code here brush : {
          toolbox : ['rect'],`enter code here`
          brushLink : [0 , 1, 2 , 3],
          brushType : 'rect',
          brushMode : ['single'],
          outOfBrush: {
              color: '#abc'
          },
          brushStyle: {
              borderWidth: 2,
              color: 'rgba(0,0,0,0.2)',
              borderColor: 'rgba(0,0,0,0.5)',
          },
          throttleDelay: 300,
      },
      toolbox : {
          show : false,
          feature : {
              brush : {
                      type :  ['rect'],
                      title : {
                          rect : 'Active Brush'
                      }
                  }
          }
      }
  </code></pre>