Dark Mode & Stream Overlay [macOS] (#315)

* dark mode & stream overlay

* removed all redundant imports

* update for the new xcode version with fixes for the new 'implicitly retains self warning'

* reworked the overlay view

* cleaning up unused variables

* small corrections

Limelight/Utility/Utils.h

@@ -6,8 +6,6 @@
 //  Copyright (c) 2014 Moonlight Stream. All rights reserved.
 //
 
-#import <Foundation/Foundation.h>
-
 @interface Utils : NSObject
 
 typedef NS_ENUM(int, PairState) {
@@ -29,4 +27,4 @@ FOUNDATION_EXPORT NSString *const deviceName;
 
 - (NSString*) trim;
 
-@end
+@end