Merge pull request #75 from JustAddWires/DMap

Set Legacy device name for latest image.
Initial, basic analogRead() support.
Added support code for the ADC on the Gen2.
Fixed bug that Pin Mode could not be set to ANALOG_PULLUP.
Added/edited comments.
Moved code from SpiController.h to .cpp.
Added support for faster SPI speed (12.5 mhz) for ADC.
Added pin attributes table for Gen1.