Remove deprecation warning from pypandoc
Remove deprecation warning from pypandoc

When running `python setup.py --name` or `python setup.py --version` we would get the following warning:

```
setup.py:12: DeprecationWarning: Due to possible ambiguity, 'convert()' is deprecated. Use 'convert_file()'  or 'convert_text()'.
  README = pypandoc.convert('README.md', 'rst')
setup.py:13: DeprecationWarning: Due to possible ambiguity, 'convert()' is deprecated. Use 'convert_file()'  or 'convert_text()'.
  CHANGES = pypandoc.convert('CHANGES.md', 'rst')
```

SurveyMonkey/pycobertura,SurveyMonkey/pycobertura