Add copyright information to .py files

This change adds explicit copyright information too python
files files.  The copyright year used in each case is the
date of the first git commit of each file.

The goal is to allow jsoncpp to be integrated into the
chromium source tree which requires license information in
each source file.

fixes #234
diff --git a/test/cleantests.py b/test/cleantests.py
index 1a4f1f1..9772d54 100644
--- a/test/cleantests.py
+++ b/test/cleantests.py
@@ -1,4 +1,10 @@
-# removes all files created during testing
+# Copyright 2007 Baptiste Lepilleur
+# Distributed under MIT license, or public domain if desired and
+# recognized in your jurisdiction.
+# See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
+
+"""Removes all files created during testing."""
+
 import glob
 import os
 
diff --git a/test/generate_expected.py b/test/generate_expected.py
index 2bbf569..0b74f51 100644
--- a/test/generate_expected.py
+++ b/test/generate_expected.py
@@ -1,3 +1,8 @@
+# Copyright 2007 Baptiste Lepilleur
+# Distributed under MIT license, or public domain if desired and
+# recognized in your jurisdiction.
+# See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
+
 from __future__ import print_function
 import glob
 import os.path
diff --git a/test/pyjsontestrunner.py b/test/pyjsontestrunner.py
index afaabd9..7f38356 100644
--- a/test/pyjsontestrunner.py
+++ b/test/pyjsontestrunner.py
@@ -1,4 +1,11 @@
-# Simple implementation of a json test runner to run the test against json-py.
+# Copyright 2007 Baptiste Lepilleur
+# Distributed under MIT license, or public domain if desired and
+# recognized in your jurisdiction.
+# See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
+
+"""Simple implementation of a json test runner to run the test against
+json-py."""
+
 from __future__ import print_function
 import sys
 import os.path
diff --git a/test/runjsontests.py b/test/runjsontests.py
index 597bf2f..d21c02f 100644
--- a/test/runjsontests.py
+++ b/test/runjsontests.py
@@ -1,3 +1,8 @@
+# Copyright 2007 Baptiste Lepilleur
+# Distributed under MIT license, or public domain if desired and
+# recognized in your jurisdiction.
+# See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
+
 from __future__ import print_function
 from __future__ import unicode_literals
 from io import open
diff --git a/test/rununittests.py b/test/rununittests.py
index dd1c9a3..08850ec 100644
--- a/test/rununittests.py
+++ b/test/rununittests.py
@@ -1,3 +1,8 @@
+# Copyright 2009 Baptiste Lepilleur
+# Distributed under MIT license, or public domain if desired and
+# recognized in your jurisdiction.
+# See file LICENSE for detail or copy at http://jsoncpp.sourceforge.net/LICENSE
+
 from __future__ import print_function
 from __future__ import unicode_literals
 from io import open