Release v0.5.4

This is another bugfix release.

• HostAPI parameter for input and output devices is now properly honored
• fixed random WdmSyncloctl error in nats server (windows)
• fixed a rarely happening race condition when writing audio samples to the sound device
• prevent the mixture of incoming audio samples when multiple users send at the same time
• each tx user has now its own independent audiocodec.Decoder which is automatically detected and set the first time a packet arrives