Bug#888918: release.debian.org: Update freeze policy for buster

[Niels Thykier <niels@thykier.net>]

Package: release.debian.org
Severity: normal

Hi,

We should update the freeze policy for buster.

The bug is 1) a reminder of this fact and 2) a reminder of some
concrete improval suggestions:

 * Remove references to priority extra (e.g. "priority: optional or extra")
 * Add a reference to the list of key packages
   => https://udd.debian.org/cgi-bin/key_packages.yaml.cgi
 * Add a more summary view of the milestones.  Example table in [1].

Thanks,
~Niels

[1] People have been asking for a summary of which milestone applies
what policy change.  The following table *could* be an example of
that.

  ------8<------ EXAMPLE ------8<------

  +---------------------+-------------------------------+---------------------+--------------------+
  | Effect \ Milestone  |       Transition freeze       |     Soft-freeze     |     Full-freeze    |
  +---------------------+-------------------------------+---------------------+--------------------+
  | Major transitions   |  No new transitions           |          No         |         No         |
  | Migration age req.  |  Standard (2/5/10d)           |     10 day delay    | Standard (2/5/10d) |
  | New src packages    |  Standard automatic migration |          No         |         No         |
  | Re-entry to testing |  Standard automatic migration |          No         |         No         |
  | Migration rules     |  Standard automatic migration | Some manual reviews | 100% manual review |
  +---------------------+-------------------------------+---------------------+--------------------+

  ------8<------ EXAMPLE ------8<------