Scripts to support Atmel SAM3 chips

[jdubois]

I looked at your updated auto.script and atmel-auto.script and it seems to do the trick to avoid the false positives in the atmel script. The only thing I did notice was that the new auto.script very slightly broke the nxp-auto.script. Just need to change the function findLPCDevice() in the nxp-auto.script to findDevice() (and the call to it in the main() function) and everything now seems to flow beautifully from the auto.script for NXP, ST, and Atmel chips (I don't have any silabs chips to test).

I'll put up a pull request on the dev branch after I've added a few more devices to the NXP detection.