Revert "update"

This reverts commit 98aca4bfd93feca9155af55819d9eec42727db60.
fix command line parameter for avr-size
Make serial work with most chips by default
Added pin mapping list to docs, useful for porting
Processor-independent pin mapping feature.

- Cleaned up and organized pin mapping concept by @elmom.

- pin_map.h allows for user-supplied pin mapping and port vector
definitions in a centralized file. With more processor types, more
definitions could be added.
Pin map definition cleanup.
remove mcu argument for avr-size in makefile as it is not present in GNU Binutils 2.22
Update Pin Change Interrupts so it works

PCIE1 - Interrupt 8 on the Mega is attached to USART0 RX so when any
serial communication was transmitted it was triggering the Reset
Interrupt