Remove sed magic to set /etc/hosts for Debian templates

Hosts file is changed according to
http://www.debian.org/doc/manuals/debian-reference/ch05.en.html#_the_hostname_resolution

boxes/debian/lxc-template

@@ -65,13 +65,19 @@ EOF
     cat <<EOF > $rootfs/etc/hostname
 $hostname
 EOF
+    # set minimal hosts
+    cat <<EOF > $rootfs/etc/hosts
+127.0.0.1   localhost
+127.0.1.1   $hostname
 
-    # set the host in case it is not set so that sudo does not complain about the host
-    if ! (grep -q $hostname $rootfs/etc/hosts); then
-      chroot $rootfs sed -i -e \
-          "s/^127.0.0.1\(\s\+\)localhost$/127.0.0.1\1localhost\n127.0.1.1\1${hostname}/g" \
-          /etc/hosts >/dev/null 2>&1 || true
-    fi
+# The following lines are desirable for IPv6 capable hosts
+::1     ip6-localhost ip6-loopback
+fe00::0 ip6-localnet
+ff00::0 ip6-mcastprefix
+ff02::1 ip6-allnodes
+ff02::2 ip6-allrouters
+ff02::3 ip6-allhosts
+EOF
 
     # set default locale
     cat <<EOF > $rootfs/etc/locale.gen