[css-forms] Add android date picker.

Author: tabatkins

css-forms/Overview.bs

@@ -134,6 +134,7 @@ especially on mobile devices where they're a bit "weirder".
 
 Time Pickers {#time-examples}
 -----------------------------
+
 <figure>
 	<img src="images/time01.png">
 	<figcaption>iOS time picker</figcaption>
@@ -148,3 +149,11 @@ Time Pickers {#time-examples}
 	<img src="images/time03.png">
 	<figcaption>Android time picker 2</figcaption>
 </figure>
+
+Date Pickers {#date-examples}
+-----------------------------
+
+<figure>
+	<img src="images/date01.png">
+	<figcaption>Android date picker</figcaption>
+</figure>