audio processing: applications moved

Signed-off-by: Samuel Casa <samuelcasa9@gmail.com>
audio processing: gitignore file added

Signed-off-by: Samuel Casa <samuelcasa9@gmail.com>
audio processing: script to convert mp3 to wav added

Signed-off-by: Samuel Casa <samuelcasa9@gmail.com>
audio processing: script to convert stereo wave files to mono wave files

Signed-off-by: Samuel Casa <samuelcasa9@gmail.com>
audio processing: readme added

Signed-off-by: Samuel Casa <samuelcasa9@gmail.com>