Fixed fixes for Python 2 & 3

I've grabbed and tested rpodgorny's changes and found that while they compile for Python 2 they didn't work.  Failing with an undefined symbol error for the missing PyInt_AS_Long method. 

I've added some potentially dirty defs to fix that, and have compiled and tested under both Python 2 and 3 by successfully driving a Display-o-Tron 3000 display from a Raspberry Pi using spidev.