works on Heltec Automation ESP32

[mahesh2000]

Just a note that the library works on Heltec's ESP32 LoRa, too. Tested on Wireless Stick Lite. Their version of ESP32 is 0.0.5. I just copied over the ulptool folder, platforms.local.txt and esp32ulp-elf-binutils, and 5 minutes later, ulp_README was running on the critter.

I still have to copy over the ulp.s file to the temp folder on a 2nd-run compilation (issue #78), otherwise it won't work. Used to, 1 year ago.