Add getLastValueType()

src/de/inetsoftware/jwebassembly/module/ValueStackManger.java

@@ -80,6 +80,15 @@ class ValueStackManger {
         return elements[size - deep - 1].codePosition;
     }
 
+    /**
+     * Get the value type of the last value on the stack.
+     * 
+     * @return the value type
+     */
+    ValueType getLastValueType() {
+        return elements[size - 1].valueType;
+    }
+
     /**
      * Ensure that there is enough capacity.
      */