deps/gtest is not Python 3 compatible

[cclauss]

$ flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics

./OpenCC/deps/gtest-1.11.0/scripts/upload.py:82:19: E999 SyntaxError: invalid syntax
    except IOError, e:
                  ^
./OpenCC/deps/gtest-1.11.0/scripts/pump.py:249:11: E999 SyntaxError: invalid syntax
    print 'ERROR: %s expected at %s.' % (token_type, pos)
          ^
./OpenCC/deps/gtest-1.11.0/scripts/gen_gtest_pred_impl.py:307:9: E999 SyntaxError: invalid syntax
  print 'Updating file %s . . .' % path
        ^
./OpenCC/deps/gtest-1.11.0/scripts/release_docs.py:130:11: E999 SyntaxError: invalid syntax
    print 'Branching %d .wiki files:' % (len(self.files_to_branch),)
          ^
./OpenCC/deps/gtest-1.11.0/test/gtest_test_utils.py:176:5: F633 use of >> is invalid with print function
    print >> sys.stderr, message
    ^
4     E999 SyntaxError: invalid syntax
5     F632 use ==/!= to compare constant literals (str, bytes, int, float, tuple)
1     F633 use of >> is invalid with print function
5