- ported test cases for EscposImage class, copied over 1px and 2px test images from escpos-php
- added test cases over image print function
- updated QR tests to also include image output check
- updated CLI to match new image function options
Expand settings on escpos.qr to include ec, size,
model and 'native' (send image or send esc/pos QR command).
Default is set as native=False, so existing code will continue to
render QR codes as images.
Michael Billington