change the rect

examples/vector/plot.html

      <li><button onclick="draw('polyline')">线</button></li>
      <li><button onclick="draw('polygon')">面</button></li>
      <li><button onclick="draw('circle')">圆</button></li>
-     <li><button onclick="draw('rectangle')">矩形</button></li>
+     <li><button onclick="draw('rect')">矩形</button></li>
      <li><button onclick="draw('attack_arrow')">进攻箭头</button></li>
      <li><button onclick="draw('double_arrow')">双箭头</button></li>
      <li><button onclick="draw('fine_arrow')">直箭头</button></li>

src/modules/plot/Plot.js

       case OverlayType.CIRCLE:
         drawWorker = new DrawCircle(style)
         break
-      case OverlayType.RECTANGLE:
+      case OverlayType.RECT:
         drawWorker = new DrawRectangle(style)
         break
       case OverlayType.BILLBOARD:
       case OverlayType.CIRCLE:
         editWorker = new EditCircle(overlay)
         break
-      case OverlayType.RECTANGLE:
+      case OverlayType.RECT:
         editWorker = new EditRectangle(overlay)
         break
       case OverlayType.BILLBOARD: