Fully pass all of nestest.nes w/ nintendulator log -- including unofficial opcodes
Properly implement mapper abstraction and specifically the NROM mapper
Mount the mapper instead of the raw prg data when initing a NES
Load PC with the reset vector on init.

I'm not sure why this seems to break nestest. I'll have to look at it later, instead just hack around it for now
Add a runner for blargg's tests
Fix stack failures where the SP wasn't wrapping around 0x0100 page correctly
instr_test-v4 working except for 4 unofficial opcodes that will take some time