#11 Defined Memory Spaces in an enum

[Robert James Kaes]

Rather than using a simple boolean to indicate whether
access is in program memory or EEPROM memory, I've
changed to a "MEMSPACE" enum to hold the distinction.
By itself, this change is rather pointless, but I'm
adding support for the fuse bits in the ATtiny2313, and
they reside outside of both program memory and EEPROM
memory. In fact they don't have a definite address
space at all, but there is a normal, high, and extended
bits, so there is an implicit addressing going on already.

[Robert James Kaes]