##ALOCenteredButton
Alexey Yachmenov <[email protected]>
ALOCenteredButton 是一个简单的 UIButton 子类，用于垂直居中布局（图片和标签）
##使用示例
ALOCenteredButton *button = [[ALOCenteredButton alloc] initWithFrame:frame];
button.buttonOrientation = ALOCenteredButtonOrientationVertical; // button orientation
button.imageLabelSpacing = 10.f; // space between title label and button image