Add Pie Chart to docs

README.md

@@ -62,7 +62,7 @@ const chart = new Chart({
     parent: '#chart',
     title: "My Awesome Chart",
     data: data,
-    type: 'bar', // or 'line', 'scatter', 'percentage'
+    type: 'bar', // or 'line', 'scatter', 'pie', 'percentage'
     height: 250
 })
 ```

docs/index.html

@@ -80,7 +80,7 @@
     parent: "#chart",
     title: "My Awesome Chart",
     data: data,
-    type: 'bar', // or 'line', 'scatter', 'percentage'
+    type: 'bar', // or 'line', 'scatter', 'pie', 'percentage'
     height: 250
   });</code></pre>
               <div id="chart-types" class="border"></div>