Implement first few screens of Android 5.0-based UI.

Source/Android/app/src/main/res/values/dimens.xml

@@ -0,0 +1,10 @@
+<resources>
+    <!-- Default screen margins, per the Android Design guidelines. -->
+    <dimen name="activity_horizontal_margin">16dp</dimen>
+    <dimen name="activity_vertical_margin">16dp</dimen>
+
+    <dimen name="diameter">48dp</dimen>
+    <dimen name="elevation_low">1dp</dimen>
+    <dimen name="elevation_high">4dp</dimen>
+    <dimen name="add_button_margin">16dp</dimen>
+</resources>