update demo
enable module for demo project
Add DOUAudioBase.h.
Add spatial and frequency analyzer.
Update example project.
DOUAudioStreamer: import DOUAudioAnalyzer+Default.
DOUAudioStreamer: add interfaces for analyzers.
DOUAudioAnalyzer: adjust level count to 20
DOUAudioStreamer: add DOUAudioStreamerIdle status
DOUAudioEventLoop: handle stop event consistently
DOUAudioStreamer: improve finished streamer handling
DOUAudioEventLoop: cleanup streamer once finished
example: handle idle status