fix fc-ltr className not being cleaned up when calendar is destroyed

src/Calendar.js

@@ -345,7 +345,7 @@ function Calendar(element, instanceOptions) {
 
 		header.destroy();
 		content.remove();
-		element.removeClass('fc fc-rtl ui-widget');
+		element.removeClass('fc fc-ltr fc-rtl ui-widget');
 	}
 	
 	

tests/automated/destroy.js

@@ -0,0 +1,27 @@
+describe('destroy', function() {
+
+	beforeEach(function() {
+		affix('#cal');
+	});
+
+	describe('when calendar is LTR', function() {
+		it('cleans up all classNames on the root element', function() {
+			$('#cal').fullCalendar({
+				isRTL: false
+			});
+			$('#cal').fullCalendar('destroy');
+			expect($('#cal')[0].className).toBe('');
+		});
+	});
+
+	describe('when calendar is RTL', function() {
+		it('cleans up all classNames on the root element', function() {
+			$('#cal').fullCalendar({
+				isRTL: true
+			});
+			$('#cal').fullCalendar('destroy');
+			expect($('#cal')[0].className).toBe('');
+		});
+	});
+
+});