Version numbering of gcc-4.3 packages

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

I did the first upload of gnat-4.3 (= 4.3-20080127-1) yesterday and
was surprised that it was rejected because the upload did not contain
the .orig.tar.gz file.  That was in turn caused by dh_genchanges
excluding the .orig.tar.gz from the .changes file.  The ultimate
culprit is the bizarre version numbering scheme involving two dashes.

Of course, I rebuilt and uploaded using dpkg-buildpackage -sa but I
should not have to do that and I think it is better to fix the problem
than work around it.

Therefore I propose we switch to using the tilde for prereleases:
4.3.0~20080127-1, etc.  Unfortunately, the ".0" is necessary to make
the next version "larger than" 4.3-20080127-1.  OTOH, the next release
of GCC will indeed be 4.3.0, not 4.3.

We can implement this scheme with the next upload.

OK?

-- 
Ludovic Brenta.