iOS7 hacks

don't resize screen on TabBarController/TableView....
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if( [self respondsToSelector:@selector(edgesForExtendedLayout)] ) {
  self.edgesForExtendedLayout = UIRectEdgeNone;
}

turn off header
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1. General --> Deployment Info --> Status Bar Style, select "Hide during application launch"
2. Info --> View controller-based status bar appearance --> NO

change UIStatusBar text color
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- viewcontroller based, add to specific viewcontroller
1. UIViewControllerBasedStatusBarAppearance to YES
2. In viewDidLoad do a [self setNeedsStatusBarAppearanceUpdate];
3. -(UIStatusBarStyle)preferredStatusBarStyle{ 
    return UIStatusBarStyleLightContent; 
   }

- for whole app 
1. UIViewControllerBasedStatusBarAppearance to NO
2. [[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleBlackTranslucent];