解决了语音上传到问题，接下来要解决下载播放问题

Pods/HappyDNS/HappyDNS/Common/QNLruCache.h

@@ -0,0 +1,23 @@
+//
+//  QNLruCache.h
+//  HappyDNS
+//
+//  Created by bailong on 16/7/5.
+//  Copyright © 2016年 Qiniu Cloud Storage. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+@interface QNLruCache : NSObject
+
+- (instancetype)init:(NSUInteger)limit;
+
+- (void)removeAllObjects;
+
+- (void)removeObjectForKey:(NSString *)key;
+
+- (id)objectForKey:(NSString *)key;
+
+- (void)setObject:(id)obj forKey:(NSString *)key;
+
+@end