tag and tarball are different (function svn_revision)

[Peter Johansson]

If I checkout the most recent tag and bootstrap, configure and build, the I will not get the same as if build from the tarball (even if I use the same versions of autotools).

The reason is that lib/subversion_info.cc will be different. In the tag function svn_revision reflects the revision of the tag, while for the tarball the function reflect the revision of the wc in which the release manager created the tarball.

With the currect ReleaseProcedure the tarball is created before tagging and consequently the tarball_rev = tag_rev - 1. I think the goal should be that a "tag build" and a "tarball build" should be as similar as possible.

Of note, the revision is (currently) only included in the report when DEV_BUILD = true, in other words, not in tags and tarballs.

[Peter Johansson]

Note that this means that checksums are not the same either, which means that a Portfile can not be reproduced from a tag but should be reproduced from the tarball (or similar)

[Peter Johansson]

We should fix this before next release.