Revert calendar default value and add documentation

modules/default/calendar/README.md

@@ -109,6 +109,13 @@ The following properties can be configured:
 				<code>
 					titleReplace: {'Birthday of ' : '', 'foo':'bar'}
 				</code>
+				<br><b>Default value:</b> 
+				<code>
+				{
+					"De verjaardag van ": "",
+					"'s birthday": ""
+				}
+				</code>
 			</td>
 		</tr>
 		<tr>

modules/default/calendar/calendar.js

@@ -32,7 +32,10 @@ Module.register("calendar", {
 				url: "http://www.calendarlabs.com/templates/ical/US-Holidays.ics",
 			},
 		],
-		titleReplace: {},
+		titleReplace: {
+			"De verjaardag van ": "",
+			"'s birthday": ""
+		},
 		broadcastEvents: true
 	},