128 word version of Optiboot for ATmega88/168

rewrite in assembler to make it fit - read HowTo

based on Optiboot (https://github.com/Optiboot/optiboot)

."Although it has evolved considerably, Optiboot builds on the original work
.of Jason P. Kyle (stk500boot.c), Arduino group (bootloader),
.Spiff (1K bootloader), AVR-Libc group and Ladyada (Adaboot).
.Optiboot is the work of Peter Knight (aka Cathedrow). Despite some
.misattributions, it is not sponsored or supported by any organisation
.or company including Tinker London, Tinker.it! and Arduino.
.Maintenance of optiboot was taken over by Bill Westfield (aka WestfW) in 2011."