add index

diff --git a/1.6/bookindex.xml b/1.6/bookindex.xml
new file mode 100755 (executable)
index 0000000..261c6ec
--- /dev/null
+++ b/1.6/bookindex.xml
@@ -0,0 +1,5 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<index xmlns='http://docbook.org/ns/docbook'>
+<title>Index</title>
+</index>
+