Shift high byte of address bus first.

The schematic at http://www.ichbinzustaendig.de/dev/meeprommer-en shows
the low-byte address bus 74HC595 (EEPROM A0..A7) connected first,
cascading into the high-byte 74HC595. This means the high byte should be
shifted first. The code comments reflect this, but the actual code
doesn't.

Note that @presslab-us's fork shifts the high byte first, although he
says he didn't specifically change the address byte order. I'm not sure
how it crept in here - probably while experimenting for a board with
the '595 chips wired in reverse.