Reduce EEPROM usage

[per1234]

The EEPROM addresses are defined in neteeprom.h in the bootloader source files.

• Remove password section. This should be implemented separately from the bootloader.
  • Write a password setting example sketch to use with NetReset.
• Store version in Flash instead of EEPROM like optiboot.
  • Files to edit:
  • main.c
  • debug - it outputs the version
  • for this to be readable the fuses need to be changed from the standard Arduino lock bit fuse values. See: http://forum.arduino.cc/index.php?topic=322325.msg2485955#msg2485955
  • http://eleccelerator.com/fusecalc/fusecalc.php shows what the different lock/unlock bit values do - see optiboot boards1.6.txt for example of correct fuse values.
• Remove SIG flags. These are used to trigger default network settings.
  • Remove default network setting code from the bootloader source.
  • w5100.h
  • tftp.c/h
  • Remove the default network setting information from the documentation
• Update the documentation of the reserved EEPROM section
• This is a major change that breaks compatibility with previously configured boards.