Add ISO week dates to the calendar

This patch adds ISO week dates to the calendar. Week dates are an
often used feature in business and government offices. Can be turned
on through gconf, off by default.

https://bugzilla.gnome.org/show_bug.cgi?id=603532

data/gnome-shell.schemas

@@ -438,6 +438,20 @@
         </locale>
       </schema>
 
+      <!-- Calendar -->
+      <schema>
+        <key>/schemas/desktop/gnome/shell/calendar/show_weekdate</key>
+          <applyto>/desktop/gnome/shell/calendar/show_weekdate</applyto>
+          <owner>gnome-shell</owner>
+          <type>bool</type>
+          <default>false</default>
+          <locale name="C">
+            <short>Show the week date in the calendar</short>
+            <long>
+              If true, display the ISO week date in the calendar.
+            </long>
+          </locale>
+      </schema>
   </schemalist>
 
 </gconfschemafile>

data/theme/gnome-shell.css

@@ -899,6 +899,10 @@ StTooltip {
     padding: 0px 4px 2px 0px;
 }
 
+.calendar-calendarweek {
+    color: #666666;
+}
+
 /* App Switcher */
 #altTabPopup {
     padding: 8px;