I discovered that there are more than one ProDOS boot block in the wild, so I
simplified the check for recoverable RAM disk to check card for $01 and then
anything besides $00 and $FF since most uninitialized RAM tends to have one of
those two values. This is slightly more rigid than the boot code checks for.
I added a jump to AppleSoft if no bootable device is found. I changed the
message a little bit, too.
I also added notes about the feasibility of using the RamFactor firmware.