KeyChain-UDID

save UDID into keyChain

• Pod接入：

    pod 'KeyChain-UDID'
    pod install
  

• 在需要使用的类中

    #import <YYQKeyChain.h>
    ...
    ...
     NSString *udid = [YYQKeyChain getUDIDWithUniqueKey:@"com.comname.app.udid.instead"];
    NSLog(@"udid from keyChain %@", udid);