几句话使用banner，完全解耦，点击事件有代理
自动滚动，手动滚动都可以
IndexBannerView *bannerView = [[IndexBannerView alloc] initWithFrame:CGRectMake(0, 20, kScreenWith, 150)];
NSArray *imgArr = @[@"1.png",@"2.png",@"3.png",@"4.png"];
bannerView.imageItemsArray = imgArr;
bannerView.delegate = self;
[self.view addSubview:bannerView];
