##FGGProgressHUD
##Producation
一个极简的HUD蒙板，直接在controller中使用，[self showHUD]
##Usage
- show:
[self showHUD];
- hide:
[self hideHUD];
like this:
- (void)viewDidLoad {
[self showHUD];
__weak typeof(self) wkself=self;
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(5 * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[wkself hideHUD];
});
}