Merge lp://staging/~sinzui/launchpad/obsolete-series-0 into lp://staging/launchpad

This is my branch to prevent timeout caused by the product-release-finder.

    lp:~sinzui/launchpad/obsolete-series-0
    Diff size:
    Launchpad bug:5
          https://bugs.launchpad.net/bugs/590806
          https://bugs.launchpad.net/bugs/490945
    Test command: ./bin/test -vv \
          -t productseries-views -t GetFiltersTestCase -t xx-project-registry
    Pre-implementation: no one.
    Target release: 10.06

prevent timeout caused by the product-release-finder
----------------------------------------------------

A review of the PRF revealed that it was downloading files and creating
released for series that belong to obsolete junk. These series are obsolete so
the PRF must ignore them. The releases were deleted when the series was moved
to obsolete junk. There are timeouts on obsolete-junks pages because there
PRF recreated information that users wanted gone.

ADDENDUM Bug #490945 [obsolete series takes precedence over stable]
    If I move milestone 1.5, for instance, to obsolete instead of stable, the
    main download page ( https://launchpad.net/kabikaboo/ ) changes the
    primary download to the newest obsolete download

Rules
-----

    * Ensure the file release glob is set to Null during series delete
    * Ensure that the series status is set to Obsolete
    * Ensure that the PRF ignores Obsolete series
    * Export releasefileglob to API so that problem series can be fixed
      before 10.06 is released.

ADDENDUM Bug #490945 [obsolete series takes precedence over stable]
    * latest_release_with_download_files() should use
      sorted_active_series_list() to filter out obsolete series.

QA
--

    * Verify that a deletes series is marked obsolete and that the
      filereleaseglob is set to None
    * Verify that the release_file_glob is visible:
        from lpscripts import lp_factory
        from launchpadlib.launchpad import (
            Launchpad, EDGE_SERVICE_ROOT, STAGING_SERVICE_ROOT)
        lp = lp_factory('edge', app_name='testing')
        project = lp.projects['gedit']
        series = project.getSeries(name='master')
        print series.name
        print series.release_file_glob

ADDENDUM Bug #490945 [obsolete series takes precedence over stable]
    * Visit a project with a release shown of the front page.
    * Mark the series obsolete
    * Verify the release changes on the front page.

Lint
----

Linting changed files:
  lib/lp/registry/browser/__init__.py
  lib/lp/registry/browser/product.py
  lib/lp/registry/browser/tests/product-files-views.txt
  lib/lp/registry/browser/tests/productseries-views.txt
  lib/lp/registry/interfaces/productseries.py
  lib/lp/registry/scripts/productreleasefinder/finder.py
  lib/lp/registry/stories/webservice/xx-project-registry.txt
  lib/lp/registry/tests/test_prf_finder.py

Test
----
    * lib/lp/registry/browser/tests/product-files-views.txt
      * Verify that obsolete releases are not shown on the project's index
        page.
    * lib/lp/registry/browser/tests/productseries-views.txt
      * Verify that the "deleted" series was marked obsolete and the
        relasefileglob was set to None.
    * lib/lp/registry/stories/webservice/xx-project-registry.txt
      * Verify that release_file_glob is exported.
    * lib/lp/registry/tests/test_prf_finder.py
      * Verify that obsolete series are not included in the finder filters.

Implementation
--------------

    * lib/lp/registry/browser/__init__.py
      * Marked the series as obsolete and clear the releasefileglob when
        the user deletes (moves) the series.
    * lib/lp/registry/browser/product.py
      * Use sorted_active_series_list in latest_release_with_download_files().
    * lib/lp/registry/interfaces/productseries.py
      * Export release_file_glob so that I can see and fix the damage.
    * lib/lp/registry/scripts/productreleasefinder/finder.py
      * Skip obsolete series.