- ATmega1284P support bootloader modifications based on
https://github.com/arjenhiemstra/SEM-Bootloader

- Add the 3 common ATmega1284P pinouts in 16Mhz full swing and low power
and internal 8Mhz configuration.

- more-boards.txt contains the additional boards for the Arduino IDE
1.0.,x version to avoid adding too many entries to the Tools > Board
menu.

The atmega2560 size in Makefile was set to 4096 words but the bootloader
is 3844 bytes so it will fit in a 2048 word boot flash section.

- Makefile corrected.

- make new Mega 2560 bootloader

- update high_fuses value in boards.txt

- Pinout correction
- digitalPinToInterrupt()

This makes it more clear what the purpose of this file is.

- Ability to disable bootloader blink
- Ability to disable SD SS pin state change
- Standard Ethernet Shield(and Ethernet library) W5100 and SD SS pins
for all ATmega1284P variants
- Remove all ATmega1284P variants except for avr_developers. This is the
only variant with a license so until I can get licenses for the others
Mighty 1284P will need to be installed to add support for those boards.
- Update documentation

NOTE: For some reason using 57600 baud rate for ATmega1284P 8MHz causes
serial upload not to work. They will only work with 115200 baud rate.
this forced me to make separate 8MHz boards entries in more-boards.txt
instead of being able to add a 8MHz option to the Clock custom menu and
using the 16MHz bootloader file at 57600.

I had removed this from the documentation when I separated all the 8MHz
boards into separate boards.txt entries(because doing the half speed
trick didn't work for ATmega1284P) but then I changed the ATmega328P
boards back to having an 8MHz Internal clock option(because I realized
that they do work) .

This makes installation easier by bundling the libraries. Test files
moved to extras folder to be more in line with the libraries
specification.

- Formatting
- Instructions for enabling TFTP client in Windows
- Troubleshooting section

See arduino/Arduino#3795

A completely different NetEEPROM library was added to Library Manager so
a unique library.properties name value for the Ariadne NetEEPROM library
is necessary to avoid spurious updatable library notifications.