- move the helper programs txlt and aout2bb to the topmost directory
- build the few files from libsa in the topmost directory
* while doing this, hunted down mysterious code expansion: It seems
that ld aligns code segments differently when linking .o's directly
than when using an archive consisting of the same files. Abuse this
effect to make the bootblock even smaller. The floppy boot block
"fdboot" is now small enough to build; add it back to the Makefile.
* while being here, remove a file which was committed by mistake.
perry