Tentative implementation using golang and CGO bindings

[cmaglie]

This is a tentative fix to bind dfu-util and libusb and make the dfu-discovery in go.

• The build flags are added as #cgo directive in main.go
• To allow compile with CGO we must copy dfu_util.c, dfuse_mem.c and quirks.c to root folder
• Some glue code to bind struct dfu_if has been added as well
• We use github.com/arduino/pluggable-discovery-protocol-handler/v2 to handle all pluggable discovery protocol