Bug#871423: libconfig-model-dpkg-perl: Update extra priority to optional priority if Standards-Version is on 4.0.1

[Salvatore Bonaccorso]

Package: libconfig-model-dpkg-perl
Version: 2.096
Severity: wishlist

If the Standards-Version is already on 4.0.1 at least, when fixing
debian/control (dpkg-control) the values of

Priority: extra

should be fixed up/migrated to

Priority: optional

This would be inline to the upgrading-checklist for 4.0.1:

   2.5

           Priorities are now used only for controlling which packages are
           part of a minimal or standard Debian installation and should be
           selected based on functionality provided directly to users (so
           nearly all shared libraries should have a priority of optional).
           Packages may now depend on packages with a lower priority.

           The extra priority has been deprecated and should be treated as
           equivalent to optional. All extra priorities should be changed to
           optional. Packages with a priority of optional may conflict with
           each other (but packages that both have a priority of standard or
           higher still may not conflict).

Salvatore