add a grab function that copies the data into a complex double float array
pylon crashes occasionally because my LANG is set to en.UTF8
i set it to C, now

usually this happens after power cycling the cameras. i have to wait for a
few seconds for the cameras to become available

martin@localhost ~/arduino_due_lisp/pylon $ ./test_pylon_wrapper
creating factory
finding devices
preparing camera array
attaching cameras
camera 0
Using device Basler acA1920-25gm#00305315DFDD#192.168.4.100:3956
camera 1
Using device Basler acA1920-25gm#00305315DFDE#192.168.5.102:3956
Camera 0: Basler acA1920-25gm#00305315DFDD#192.168.4.100:3956
GrabSucceeded: 1
SizeX: 1024
SizeY: 1024
Gray value of first pixel: 9

Camera 1: Basler acA1920-25gm#00305315DFDE#192.168.5.102:3956
GrabSucceeded: 1
SizeX: 600
SizeY: 600
Gray value of first pixel: 11

Camera 0: Basler acA1920-25gm#00305315DFDD#192.168.4.100:3956
GrabSucceeded: 1
SizeX: 1024
SizeY: 1024
Gray value of first pixel: 9

max(Width)=1468
1468
min(Width)=64
64
inc(Width)=1
1
17563654
0 Mono8
1 Mono12
2 Mono12Packed
3 YUV422Packed
4 YUV422_YUYV_Packed
Mono12Packed
improve documentation of arduino-serial-sbcl