debian packaging: bump version to debhelper compat level 9

debian/compat

@@ -1 +1 @@
-8
+9

debian/control

@@ -3,7 +3,7 @@ Section: shells
 Priority: extra
 Maintainer: ridiculous_fish <corydoras@ridiculousfish.com>
 Uploaders: David Adam <zanchey@ucc.gu.uwa.edu.au>
-Build-Depends: debhelper (>= 8.0.0), libncurses5-dev, autoconf, autotools-dev, dh-autoreconf, gettext
+Build-Depends: debhelper (>= 9.0.0), libncurses5-dev, autoconf, autotools-dev, dh-autoreconf, gettext
 # When libpcre2-dev is available on all supported Debian versions, add a dependency on that.
 Standards-Version: 3.9.4
 Homepage: http://fishshell.com/

debian/rules

@@ -4,18 +4,14 @@
 # Uncomment this to turn on verbose mode.
 export DH_VERBOSE=1
 
-# dpkg-dev 1.16.1 doesn't export buildflags
-# can be removed once on dh compat level 9
-DPKG_EXPORT_BUILDFLAGS = 1
--include /usr/share/dpkg/buildflags.mk
-DEB_DISTRIBUTION = $(shell dpkg-parsechangelog | sed -n -e 's/^Distribution: //p')
-
 %:
 	dh $@ --with autotools-dev,autoreconf
 
 override_dh_installdocs:
 	dh_installdocs --link-doc=fish
 
+# Still needed until all platforms have debhelper 9.20151219
+# Consider transitioning https://wiki.debian.org/DebugPackage
 override_dh_strip:
 	dh_strip --dbg-package=fish-dbg