Merge product series +ubuntupkg and +addpackage pages

[Guilherme Salgado]

These two pages must share the same code.

Why do they have different permissions?

When fixing this bug please get rid of PackagingUtil from database/packaging.py, since we can do all that with the public API of ProductSeries.

[Matthew Paul Thomas (mpt)]

See also bug 46572, bug 83357, and bug 89392.

[Guilherme Salgado (salgado)]

The new page, when viewed from an upstream (IProduct rather than IProductSeries as it is currently) context, should allow the user to specify the product series, the distribution release and the sourcepackage name.

When viewed from a sourcepackage (IDistributionSourcePackage) the user will be able to specify the distribution release and the product series to link to.

As a bonus, from the upstream context, if there is no tarball information provided for any series:
      Launchpad can automatically infer packaging links for you. All
      we need is a download directory URL for Firefox releases:
            [Firefox 1.0 |v] [http://releases.mozilla.org/firefox/1.0 ]

[Guilherme Salgado (salgado)]

If an existing packaging entry is present for the other end of the link, we stop the user: he shouldn't be allowed to overwrite an existing primary packaging link. This would actually be valid when a package was renamed within a release, but that might be best ignored here.

[Francis J. Lacoste (flacoste)]

See some other notes discussed in London in June 2007: https://launchpad.canonical.com/200706LPMTG/notes#managing-existing-packaging-information

[David Allouche (ddaa)]

Not making it to 1.1.10. Postponing to 1.1.11.

[Francis J. Lacoste (flacoste)]

The notes were moved to https://launchpad.canonical.com/TeamLeadMeetings/200706TLMTG/notes#managing-existing-packaging-information