Integrate recent changes from Google-internal code tree.  See CHANGES.txt
for details.

diff --git a/CONTRIBUTORS.txt b/CONTRIBUTORS.txt
index 259a6f7..8adb1ff 100644
--- a/CONTRIBUTORS.txt
+++ b/CONTRIBUTORS.txt
@@ -18,6 +18,7 @@
   Petar Petrov <petar@google.com>
 
 Large code contributions:
+  Jason Hsueh <jasonh@google.com>
   Joseph Schorr <jschorr@google.com>
   Wenbo Zhu <wenboz@google.com>
 
@@ -38,7 +39,7 @@
   Kevin Ko <kevin.s.ko@gmail.com>
     * Small patch to handle trailing slashes in --proto_path flag.
   Johan Euphrosine <proppy@aminche.com>
-    * Small patch to fix Pyhton CallMethod().
+    * Small patch to fix Python CallMethod().
   Ulrich Kunitz <kune@deine-taler.de>
     * Small optimizations to Python serialization.
   Leandro Lucarella <llucax@gmail.com>