* Adds the SoundSystem static proxy class for the AudioSystem.
Added a shared IAudioSystem interface for the future.
* Moved ConnectedClient property from IPlayerSession down to ICommonSession.
* Connected up the SoundSystem to the client/server AudioSystems.
* Converted client calls over to the new system.
* Marked the old serverside functions to play sound obsolete, use the new ones from the IAudioSystem.
* Added ISharedPlayerManager to the IoC registration.