[tex-live] checks for right file types (was: testing TL'08)

[Karl Berry]

    >     texmf-dist/fonts/map/vtex/bera/bera.ali
    don't know why we need .ali files in TL. Perhaps we can strip that.

If I was starting now, I would not add .ali files, but it seems harmless
to keep them, and then users' old vtex installations will keep working.
Maybe the set of such users is empty, I dunno.

Also, it would be a little work to change the updating mechanism to
ignore them.  Doesn't seem like a priority.

Thanks,
k