**/*.py: use /usr/bin/env to find python

tests/abi_corpus/corpus_utils.py

-#!/usr/bin/python
+#!/usr/bin/env python
 # Copyright (c) 2012 The Native Client Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import codecs
 import hashlib
 import json
 import math
 import os
 import shutil
@@ skipping 338 matching lines @@
       # Our alternate validators don't currently cover everything.
       # For now, don't fail just emit warning (and a tally of failures).
       print '@@@STEP_TEXT@FAILED %d times (%.1f%% are incorrect)@@@' % (
           self.failures, self.failures * 100 / (self.successes + self.failures))
       if warn_only:
         print '@@@STEP_WARNINGS@@@'
       else:
         raise FailedTests('FAILED %d tests' % self.failures)
     else:
       print 'SUCCESS'