The AVR Dragon, previously the cheapest debugger/programmer for AVR, is out of
production. The default debugger for AVR devices has been changed to the Atmel
ICE, the now cheapest debugger option. The commit updates the documentation
accordingly.
Additionally the default programmer is changed to the Atmel ICE for consistency.
The doc is updated accordingly.
- avrdude.mk and serial.mk were included twice.
- The former resulted in `make flash` wasting one flash cycle by flashing
the same firmware twice
- Fixed typos (atmega328p instead of atmega1284p)
The ATmega1284P can be run on a breadboard with no external components, except
for a power supply and (if access to the serial is required) an USB-TTL adapter.
This commit adds it as a "board".
