Write the changelog entry for the switch to debhelper 7.

debian/changelog

@@ -8,6 +8,24 @@ openexr (1.6.1-4) unstable; urgency=low
      - Update Vcs-{Git,Browser}.
      - Remove XS-X-Collab-Maint field, no longer relevant. Patches are
        still welcome, though!
+  * Switch to debhelper 7:
+     - Bump debian/compat to 7.
+     - Version the B-D on debhelper: >= 7.0.50 to allow the use of
+       overrides.
+     - Specify some overrides to tweak as needed for the build:
+        - dh_auto_configure: pass the --with-openexr flag to configure
+          script.
+        - dh_auto_test: don't run “check” on arm and ia64 for now, and
+          bypass dh_auto_test due to bad target detection.
+        - dh_compress: no longer compress .h/.cpp examples.
+        - dh_link: needed since libopenexr-dev's and openexr's /us/s/d
+          directories are symlinks to libopenexr6's one.
+        - dh_makeshlibs: keep on using -V.
+        - dh_installdeb: add a call to dh_buildinfo to keep on storing the
+          versions of packages installed during the build.
+     - Specify some targets:
+        - build and clean to handle patching/unpatching and
+          updating/cleaning config.{guess,sub}.
 
  -- Cyril Brulebois <kibi@debian.org>  Sat, 11 Apr 2009 22:00:04 +0200