TST: BOM in test_ujson.py?
Is there some reason that `test_ujson.py` starts with a UTF-8 BOM, or was it introduced accidentally?  Can't think of why you'd want one there, but maybe I'm missing something.

```
>>> open("test_ujson.py").readline()
'\xef\xbb\xbffrom unittest import TestCase\n'
```
