Add new doxygen test doxygen_code_blocks

This does somewhat more detailed testing of the code block parsing,
and also exercises the language identification of python doctest
features.  For now, it is only tested by python (javadoc translation
may not correctly handle some of the characters that are used here).

Examples/test-suite/python/doxygen_code_blocks_runme.py

@@ -0,0 +1,53 @@
+import doxygen_code_blocks
+import inspect
+import string
+import sys
+import comment_verifier
+
+comment_verifier.check(inspect.getdoc(doxygen_code_blocks.function),
+    """\
+Test for code blocks
+
+.. code-block:: c++
+
+    simple code block
+
+More advanced usage with C++ characters:
+
+.. code-block:: c++
+
+    std::vector<int> first;                                // empty vector of ints
+    std::vector<int> second (4,100);                       // four ints with value 100
+    std::vector<int> third (second.begin(),second.end());  // iterating through second
+    std::vector<int> fourth (third);                       // a copy of third
+     // the iterator constructor can also be used to construct from arrays:
+    int myints[] = {16,2,77,29};
+    std::vector<int> fifth (myints, myints + sizeof(myints) / sizeof(int) );
+
+    std::cout << "The contents of fifth are:";
+    for (std::vector<int>::iterator it = fifth.begin(); it != fifth.end(); ++it)
+      std::cout << ' ' << *it;
+    std::cout << '\\n';
+
+A code block for C:
+
+.. code-block:: c
+
+    printf("hello world");
+
+A code block for Java:
+
+.. code-block:: java
+
+    public class HelloWorld {
+        public static void main(String[] args) {
+            // Prints "Hello, World" to the terminal window.
+            System.out.println("Hello, World");
+        }
+    }
+
+A code block for python:
+
+.. code-block:: python
+
+    print('hello world')""")