New source package uploads to `unstable' allowed

[Ian Jackson <ian@chiark.chu.cam.ac.uk>]

You may now upload packages in the new source format to `unstable'.
Packages in `stable' will continue to be in the old format.

Note that the caveats in my release announcement on debian-changes for
1.3.8 apply:

* The new source tools have not been very well tested and will have
  bugs, some probably serious.

* The source format is not entirely fixed yet.  You may need to make
  significant changes.  You _will_ need to keep up with minor
  documentation changes and _will_ need to make at least one further
  release when the format is finalised as the Standards-Version value
  will be changed.  However, building releases is a lot easier now :-)
  and you don't have to re-upload the original source tarfile part of
  the source more than once per upstream version.

I shall probably declare the new format official on Sunday.

Ian.