* Refactor the friend namespace and UInt128
This commit also:
- Fix GetFriendsList arguments ordering.
- Add GetFriendListIds.
- Expose the permission level of the port instance.
- InvalidUUID => InvalidArgument
* friend: add all cmds as commments
* add Friend structure layout
* Rename FriendErr to FriendError
* Accurately implement INotificationService
* Fix singleton lock of NotificationEventHandler
* Address comments
* Add comments for IDaemonSuspendSessionService cmds
* Explicitly define the Charset when needed
Also make "Nickname" a string
* Address gdk's comments
