Added files to recover firmware using OpenOCD with a JTAG adapter

[adeguet1]

Files pulled from https://github.com/keshuaixu/mechatronics-firmware-rescue

[pkazanzides]

I don't think we should do it this way. I wouldn't add the two bit files, since they are outdated, and would instead document that they should download from the latest release. There were other changes we discussed, such as eliminating the PROM programming -- I see that you didn't check in bscan_spi_xc6slx45.bit, which is good, but we can also remove the related code from openocd.cfg. We can also get rid of program_fpga in openocd.cfg because we should always specify the filename. That will also simplify program_fpga.sh. Finally, in the ReadMe, I would mention that you can program over Ethernet or Firewire (not just Firewire).

[adeguet1]

At that point, should I just give instructions and provide some code to copy/paste in the documentation? It seems we're almost down to a small config file, udev rules and a one line script.

[pkazanzides]

Yes, that is what I was expecting.