r392: * DH_COMPAT=3 now enables the following new features which I can't just

r392:    * DH_COMPAT=3 now enables the following new features which I can't just
     turn on by default for fear of breaking backwards compatability:
     - dh_makeshlibs makes the postinst/postrm call ldconfig. Closes: #77154
       Patch from Masato Taruishi <taru@debian.org> (modified). If you
       use this, be sure dh_makeshlibs runs before dh_installdeb; many
       old rules files have the ordering backwards.
     - dh_installdeb now causes all files in /etc to be registered as
       conffiles.
     - debian/README is now supported: it is treated exactly like
       debian/README.Debian. Either file is installed as README.Debian in
       non-native packages, and now as just README in native packages.
       Closes: #34628
   * This is really only the start of the changes for v3, so use with
     caution..
   * dh_du has finally been removed. It has been deprecated for ages, and
     a grep of the archive shows that nothing is using it except biss-awt
     and scsh. I filed bugs on both almost exactly a year ago. Those bugs
     should now be raised to severity important..
   * --number option (to dh_installemacsen) is removed. It has been
     deprecated for a while and nothing uses it. Use --priority instead.