Notes on Triggering

Added some minor notes on triggering the camera (do images work on GitHub?), since it took me a while to figure out the TRIG_PERIOD. The link in triggering.md sets the camera trigger so that it's in a "reasonable" state.
Changed output

Output of Switch.py is more clear on what to do with the new POE adapter of the monochrome Elphel cam
Num Lock done right

Since `apt-get install numlockx` didn't help over reboots, trying to use the method where we edit the keyboard config
Pointer stuff

Save current current frame pointer as a global read pointer after reading first image. Then call torp/prev/prev/prev/bimg to set frame pointer to global read pointer, move three frames previous and read the whole image from the cams memory
Further tries

This is the version with which I've asked for help on elphel-support mailing list
GPIO

Renamed GPIO.py to GPIO_output.py. Tiny script GPIO_input reads input on a desired pin. This works fine with the triggered output signal of the camera (which would go to the blue LED on the cable). We can detect triggers from the camera on the Pi, jupi!
Ingoring calculator settings