isWhite, isLower, isUpper, toLower, and toUpper now have Ascii in their
name, which matches what std.unit does with its versions of those
functions. Hopefully, it should also reduce bugs due to using the wrong
function between the ASCII and unicode versions by making the difference
more obvious.
I added std.uni.isWhite, fixed the functions so that they returned bool
instead of int, and made a few other tweaks (including reformatting
some of the code which was nigh-on-unreadable with the very odd
indentation choices that had been made with it).
Unfortunately, the change from int to bool was made with the old
functions rather than with new ones, since the names were already good
for those functions. But the code breakage is likely to be minimal,
since the return values were always 1 or 0 and meant to be used as
boolean values. I expect that the code breakage from that will be
far smaller (possibly completely non-existent) than it would have been
to create new functions with different names which returned bool. And
since the names are good as they are, it wouldn't have been nice to
rename them anyway.
