DJAlignedImageView是继承UIView,用户可以设置图片在view中排列方式. 
左
- DJImageViewHorizontallyAlignmentLeftDefault 中
- DJImageViewHorizontallyAlignmentCenter右
- DJImageViewHorizontallyAlignmentRight
上
- DJImageViewVerticallyAlignmentTopDefault 中
- DJImageViewVerticallyAlignmentCenter下
- DJImageViewVerticallyAlignmentBottom
以上排列方式在contentMode 是 AspectFit, AspectFill or ScaleToFill 时有效







