adjust button behavior

index.html

@@ -19,14 +19,14 @@
                 </path>
             </svg>
             Click to upload image
-            <label id="example">(or try example)</label>
+            <label id="clear-points">(or try example)</label>
         </label>
         <canvas id="mask-output"></canvas>
     </div>
     <label id="status"></label>
     <div id="controls">
         <button id="reset-image">Reset image</button>
-        <button id="clear-points">Clear points</button>
+        <button id="example">Clear points</button>
         <button id="cut-mask" disabled>Cut mask</button>
     </div>
     <p id="information">