Add 'Move a feature along a line' example

examples/feature-move-animation.html

@@ -0,0 +1,24 @@
+---
+template: example.html
+title: Animate a feature movement
+shortdesc: Demonstrates how to move a feature along a line.
+docs: >
+  This example shows how to use <b>postcompose</b> and <b>vectorContext</b> to
+  animate a (marker) feature along a line. In this example an encoded polyline
+  is being used.
+tags: "animation, feature, postcompose, polyline"
+---
+<div class="row-fluid">
+  <div class="span12">
+    <div id="map" class="map"></div>
+  </div>
+</div>
+<div class="row-fluid">
+  <div class="span12">
+    <label for="speed">
+      speed:&nbsp;
+      <input id="speed" type="range" min="10" max="999" step="10" value="60">
+    </label>
+    <button id="start-animation">Start Animation</button>
+  </div>
+</div>