Initial SAV MkI (RepRap CloneWars board) integration.

Included support for BT dongle on AT90USB boards.
Added LCD Shift Register LCD control
Included support for RepRap Clone Wars project board (SAV MKI).
Corrected LCD only error

If only an LCD is defined and no menu or keyboard defined, there is a
compilation error.

Added conditional compilation.
Added BT support on AT90USB devices

Added AT90USB device BT connectivity support using second UART.
Merge pull request #640 from fmalpartida/SAV-MkI

Added support for BT on AT90USB devices, corrected LCD bug, added new board and LCD