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- Make `CSVRenderer.render` return bytes, and `CSVParser.parse` expect a byte
stream.
- Have data-less renders print header row, if header is explicitly supplied
- Drop Django 1.7 tests and add Django 1.10 tests
- have `CSVRenderer.tableize` act as a generator when possible (i.e., when a
header is explicitly specified).
- Add docs for labels thanks to radyz
- Fix header rendering in `CSVStreamingRenderer` thanks to radialnash
- Improve unicode handling, thanks to brandonrobertz