Remove Support for iOS 7 (#2930)

* Drop support for iOS 7

* Copy reference images

* Update deployment for sample projects

* Update version

* Update "Life Without Cocoapods"

AsyncDisplayKit/ASRunLoopQueue.h

@@ -11,9 +11,11 @@
 //
 
 #import <Foundation/Foundation.h>
+#import <AsyncDisplayKit/ASBaseDefines.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
+AS_SUBCLASSING_RESTRICTED
 @interface ASRunLoopQueue<ObjectType> : NSObject
 
 /**
@@ -37,6 +39,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 @end
 
+AS_SUBCLASSING_RESTRICTED
 @interface ASDeallocQueue : NSObject
 
 + (instancetype)sharedDeallocationQueue;