Sometime long ago, prior 2009, tidy cleaned ALL leading, trailing spaces
from attribute values, thus can no longer distinguish between a fully
blank value like "", and a value consisting of all spaces like " ".
So in these two tests, there is a preceeding test which tests the blank case,
and tidy reports it as blank, but will no longer report the all spaces as
all spaces, but repeats the blank case.
Have amended the accesscases.txt to reflect what tidy has output for more
than the last 6+ years...