Add license statement to setup.py to resolve #50.

Google originally released pyfakefs under Apache version 2.0, and I have
reiterated that here.
diff --git a/COPYING b/COPYING
index d645695..67db858 100644
--- a/COPYING
+++ b/COPYING
@@ -173,30 +173,3 @@
       defend, and hold each Contributor harmless for any liability
       incurred by, or claims asserted against, such Contributor by reason
       of your accepting any such warranty or additional liability.
-
-   END OF TERMS AND CONDITIONS
-
-   APPENDIX: How to apply the Apache License to your work.
-
-      To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "[]"
-      replaced with your own identifying information. (Don't include
-      the brackets!)  The text should be enclosed in the appropriate
-      comment syntax for the file format. We also recommend that a
-      file or class name and description of purpose be included on the
-      same "printed page" as the copyright notice for easier
-      identification within third-party archives.
-
-   Copyright [yyyy] [name of copyright owner]
-
-   Licensed under the Apache License, Version 2.0 (the "License");
-   you may not use this file except in compliance with the License.
-   You may obtain a copy of the License at
-
-       http://www.apache.org/licenses/LICENSE-2.0
-
-   Unless required by applicable law or agreed to in writing, software
-   distributed under the License is distributed on an "AS IS" BASIS,
-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-   See the License for the specific language governing permissions and
-   limitations under the License.
diff --git a/setup.py b/setup.py
index 6a76b50..d2321bf 100644
--- a/setup.py
+++ b/setup.py
@@ -1,4 +1,21 @@
 #! /usr/bin/env python
+'''
+Copyright 2009 Google Inc. All Rights Reserved.
+Copyright 2014 Altera Corporation. All Rights Reserved.
+Copyright 2014-2015 John McGehee
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+'''
 
 from fake_filesystem import __version__