Add nano proto authors and update LICENSE file to include Android.mk.

CONTRIBUTORS.txt

@@ -17,6 +17,12 @@ Proto2 Python primary authors:
   Will Robinson <robinson@google.com>
   Petar Petrov <petar@google.com>
 
+Java Nano primary authors:
+  Brian Duff <bduff@google.com>
+  Tom Chao <chaot@google.com>
+  Max Cai <maxtroy@google.com>
+  Ulas Kirazci <ulas@google.com>
+
 Large code contributions:
   Jason Hsueh <jasonh@google.com>
   Joseph Schorr <jschorr@google.com>

LICENSE

@@ -8,6 +8,8 @@ This license applies to all parts of Protocol Buffers except the following:
     src/google/protobuf/stubs/atomicops_internals_aix.h.
     This file is copyrighted by Bloomberg Finance LP.
 
+  - Andorid.mk, which is copyrighted by The Android Open Source Project.
+
 Copyright 2014, Google Inc.  All rights reserved.
 
 Redistribution and use in source and binary forms, with or without