Some refectoring to match output path names
Make input buffer Stereo only

This way the engine has not to deal with mono samples. Mono channels are converted into Stereo in soundmanager.
Moved composeInputBuffer and clearInputBuffer to SoundDevice to match with the output path
use m_inputParams directly
fixed right channel from previous commit
removed CircularBuffer from input engines. This is not reqired anymore because of sync at device level