add multiple_inheritance example from Salvaire. It's working

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk@6577 626c5289-ae23-0410-ae9c-e8d60b6d4f22

SWIG/Examples/perl5/multiple_inheritance/example.h

@@ -0,0 +1,32 @@
+/* File : example.h */
+
+#include <iostream>
+
+using namespace std;
+
+class Bar
+{
+ public:
+  virtual void bar ()
+    {
+      cout << "bar" << endl;
+    }
+};
+
+class Foo
+{
+ public:
+  virtual void foo ()
+    {
+      cout << "foo" << endl;
+    }
+};
+
+class Foo_Bar : public Foo, public Bar
+{
+ public:
+  virtual void fooBar ()
+    {
+      cout << "foobar" << endl;
+    }
+};