Use dh_prep instead of "dh_clean -k"

Use dh_prep instead of "dh_clean -k" (dh-clean-k-is-deprecated). However
do not replace instances of dh_clean without -k option. (Debian
bug590244). Build-Depend on debhelper 7.

debian/changelog

@@ -6,6 +6,9 @@ wmaker (0.92.0-9) unstable; urgency=low
       debhelper-but-no-misc-depends)
     + [debian/control] Move homepage from description text to homepage
       field. (Lintian description-contains-homepage)
+    + Use dh_prep instead of "dh_clean -k" (dh-clean-k-is-deprecated). However
+      do not replace instances of dh_clean without -k option. Closes: #590244
+    + Build-Depend on debhelper 7.
   * Invoke ./configure mit correct --build argument, as per
      /usr/share/doc/autotools-dev/README.Debian.gz.
 

debian/control

@@ -3,7 +3,7 @@ Section: x11
 Priority: optional
 Maintainer: John H. Robinson, IV <jaqque@debian.org>
 Standards-Version: 3.8.0.1
-Build-Depends: debhelper (>= 4), automake1.4, gettext, dctrl-tools,
+Build-Depends: debhelper (>= 7.0.15), automake1.4, gettext, dctrl-tools,
  libfontconfig1-dev, libjpeg-dev, libpng12-dev, libsm-dev, libtiff4-dev,
  libtool, libgif-dev, libx11-dev, libxext-dev, libxft-dev, libxinerama-dev,
  libxkbfile-dev, libxpm-dev, libxt-dev, libxrender-dev, sharutils, libxmu-dev

debian/rules

@@ -194,12 +194,12 @@ clean:
 binary-indep: build
 #	dh_testdir -i
 #	dh_testroot
-#	dh_clean -i -k
+#	dh_prep -i
 
 binary-arch: build
 	dh_testdir -a
 	dh_testroot
-	dh_clean -a -k
+	dh_prep -a
 	dh_installdirs -a
 	debian/rules install-wmaker-stamp
 	debian/rules debian/$(LIBWRASTER)-dev.files