* refactor g2p egs

* add sha-bone; remove avg.sh from egs;

* add an example to convert transcription to pinyin with pypinyin and jieba

* format code

* 1. remove script for data downloading, since Baker dataset is not easily downloaded via terminal;
2. remove pypinyin as an extra requirement; it is alreay required by the main project;
3. clean code.

* change output format