v1.1 ROM emulation working

Updates to the original v1.0 board. These were done by hand modifying, I didn't get this design fabricated.

The 2 ZX->Pico level shifters were removed since experimentation shows they're not required. Pico GPIOs are 5V tolerant when used as inputs. Using /RD as direction for the data bus level shifter was wrong, the shifter took the bus when RAM reads happened. oops. That's now driven from ROM_READ_INV and works correctly. Transistor Q1 footprint fixed.