call fetchEventSources from fetchEvents

src/EventManager.js

@@ -68,13 +68,7 @@ function EventManager(options) { // assumed to be a calendar
 	function fetchEvents(start, end) {
 		rangeStart = start;
 		rangeEnd = end;
-		cache = [];
-		var fetchID = ++currentFetchID;
-		var len = sources.length;
-		pendingSourceCnt = len;
-		for (var i=0; i<len; i++) {
-			fetchEventSource(sources[i], fetchID);
-		}
+		fetchEventSources(sources, true);
 	}