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/scons-tools/globtool.py b/scons-tools/globtool.py
index ea7db2d..890f1b7 100644
--- a/scons-tools/globtool.py
+++ b/scons-tools/globtool.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
+
 import fnmatch
 import os
 
diff --git a/scons-tools/srcdist.py b/scons-tools/srcdist.py
index 663a234..fe1d746 100644
--- a/scons-tools/srcdist.py
+++ b/scons-tools/srcdist.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
+
 import os
 import os.path
 from fnmatch import fnmatch
diff --git a/scons-tools/substinfile.py b/scons-tools/substinfile.py
index 33e5de0..c620442 100644
--- a/scons-tools/substinfile.py
+++ b/scons-tools/substinfile.py
@@ -1,3 +1,8 @@
+# Copyright 2010 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
+
 import re
 from SCons.Script import *  # the usual scons stuff you get in a SConscript
 import collections
diff --git a/scons-tools/targz.py b/scons-tools/targz.py
index 6a4f3fa..8e5ba83 100644
--- a/scons-tools/targz.py
+++ b/scons-tools/targz.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
+
 """tarball
 
 Tool-specific initialization for tarball.