Ammend bin/cat/cat.c so the output is the same aside
from blank lines being numbered or unnumbered, depending on whether cat
was invoked with -ne or -be.
At present, when cat is invoked with -be, there is an aditional
difference that the '$' on blank lines is placed on the far left of the
Discussed in bug 210607.
While here, revert the workaround from r304035 which skipped the unit test for
this issue previously.