more work on Relax-NG, implementing interleave augmented/updated the

* relaxng.c: more work on Relax-NG, implementing interleave
* test/relaxng/* result/relaxng/*: augmented/updated the
  regression tests
Daniel
diff --git a/test/relaxng/tutor8_3.rng b/test/relaxng/tutor8_3.rng
new file mode 100644
index 0000000..b68814d
--- /dev/null
+++ b/test/relaxng/tutor8_3.rng
@@ -0,0 +1,9 @@
+<element name="content" xmlns="http://relaxng.org/ns/structure/1.0">
+  <interleave>
+    <text/>
+    <element name="p">
+      <text/>
+    </element>
+  </interleave>
+</element>
+