D-Bus API: added update script for docbook XSL

Script which might come handy for updating our copy of the docbook
XSL files.

build/xsl-update.sh

@@ -0,0 +1,15 @@
+#! /bin/sh
+#
+# Download current version of all our docbook XSL files.
+# Handles download errors by retrying. Does not handle
+# new or removed files, that needs to be done manually.
+
+set -x
+cd `dirname $0`/xsl
+for i in `find * -type f`; do
+    for attempt in `seq 0 10`; do
+        if wget -O $i.tmp http://docbook.sourceforge.net/release/xsl/current/$i && mv $i.tmp $i; then
+            break
+        fi
+    done
+done