add additional pins to avr2560 for rambo lcd
add pins for rambo lcd
add rambo arduino addons
Merge pull request #572 from ultimachine/rambo_LCD

RAMBo LCD Support, Additional Pins, and Arduino add ons
Add duplication and auto-park mode for dual x-carriage support.
Add .gitignore change to ignore .bak files (produced by WinMerge and other editors)
Merge pull request #575 from buildrob101/DualXCarriageMerge

Add duplication and auto-park mode for dual x-carriage support.
Merge branch 'Marlin_v1' into mendel90