Merge "cts_audio work: initial code - volume calibration and THD test case...

Merge "cts_audio work: initial code - volume calibration and THD test case work tuned. - 59 unit tests pass - local audio playback / recording works : uses tinyalsa - host to device ptorocol in host side implemented / tested (with loopback) - device side recording / playback works for test cases / test_io.xml - python processing baseline added. - spectrum algorithm implementated: calculate Transfer Function of device   over host and check if amplitudes are within margain. Needs parameter tuning - spectrum test needs some improvements due to the non-flat response from   ref microphone." into jb-dev