RaspiCam:

Restructured the component creation to return status codes

Added a missing function header commment
RaspiCam: Added timelapse mode to RaspiStillYUV
Fixed up EXIF setting as sending data whilst encoder port was active
is not allowed. Now close port between captures to allow setting.
hello_audio: better support for multichannel
Merge pull request #55 from JamesH65/camera_dev

Component creation functions changed to return status
hello_audio: support different sample rates
Fixed up so RAW works for each capture in timelapse mode
Merge pull request #57 from JamesH65/camera_dev

Fixed up so RAW works for each capture in timelapse mode