cloned targets rpi2dng.o and rpi2dng from raspi_dng.o and raspi_dng
Initial commit

This is a clone from raspi_dng with conversion code refactored to a new
function 'processFile'.
added rpi2dng, removed raspiraw
Changed commandline interface

Use getopt to make the command more unix-like. The command can now
process more than one input file at a time.
Major code-cleanup

Reordered code, removed unnessary statements and comments.
updated for version 2.3