Fixed word spelling at #pragma

MJRefresh/Custom/Header/MJRefreshNormalHeader.m

@@ -46,7 +46,7 @@ - (void)setActivityIndicatorViewStyle:(UIActivityIndicatorViewStyle)activityIndi
     [self setNeedsLayout];
 }
 
-#pragma makr - 重写父类的方法
+#pragma mark - 重写父类的方法
 - (void)prepare
 {
     [super prepare];