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- add a new staticmethod which can convert pinyin to upper, lower or capitalize.
https://github.com/lxneng/xpinyin/pull/28
- Removed extraneous "!" being appended to non 'a' vowel replacements when show_tone_marks=True; also added simple unitest.main() for non-nose users
https://github.com/lxneng/xpinyin/pull/30