Move RPI camera-controlling code into new pycamera package.
Split it into separate files to handle webcams vs. the pi
camera module. Make a start at a standard camera API.
Code to drive a camera via gphoto2
Initial changes to work with the new pycamera package.
Not tested much, still needs lots of work.
Make it work with Raspberry Pi, either with Pi Camera or gphoto.
Haven't tested webcam.
Guard against using output file of - if use_tmp_file
is True, since that won't work as expected with gphoto2.
Flush stdout after each iteration, so we can tail the log
Print date and time on each (verbose) iteration.
Change some comments and debug prints.