reverted automatic-verison-number

[Graham Percival]

I have reverted the automatic-version-number patch in order to
continue working on the docs.  Please do NOT re-apply this
patch until you are certain it works with GUB doc-building.

I'm not quite certain what problem this is trying to solve,
anyway.  As it is currently, the version strings indicate the
last convert-ly operation on the docs.  They get updated
automatically whenever we run convert-ly, so AFAIK there's
no problem.

- Graham