https://github.com/dataxpress/UICountingLabel
// 正常初始化
label = [[UICountingLabel alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
label.format = @"%d";// 设置数据格式
[self.view addSubview:label];
// 变化
[label countFrom:10 to:1234 withDuration:3];
