HID emulation for USB Armory

Last month (and I just noticed…), Collin Mulliner updated the USB Armory github project with some HID emulation code:

The project includes a few scripts, including:
* hidonly.sh : switches the usbarmory to be usb hid gadget
* hidnet.sh : switches the usbarmory to be a usb hid and usb ethernet gadget
* button_setup.sh : switches pin 3 and 4 to in and out
* button.sh : checks if pin 3 and 4 are connected

More info:
https://github.com/crmulliner/hidemulation