1.1.1 - Optiboot, and fix for the mysterious kitting issue in 1.1.0

Well, 1.1.0 suffered some kitting problems and was pretty much DOA. It shows the care and attention paid to testing the board manager releases over here. 1.1.1 fixes the bugs that made 1.1.0 unusable in board manager release, and the missing bootloader file for the xy4 with reset enabled is now present. But this isn't just a bugfix release- this also fortuitously pulled in a couple of additional exciting changes:

• Add support for printf to printable library (#112)
• Add menus for I2C and SPI pin mapping (#110)
• Correct bug with UART pin mapping menu and xy4/xy6/xy7 Optiboot board definitions
• Correct bug with digitalPinHasPWM macro on xy2
• Add the PIN_Pxn defines, which resolve to the arduino pin number of the specified pin.
• Various documentation enhancements, including an expanded section on Optiboot
• Update datasheet links to point to latest datasheet version. This should get rid of all the preliminary datasheet links.
• Add row in entry in part-specific doc pages listing available flash after installing Optiboot on all parts.

This is the version for board manager installation