update README.md

Author: yistLin

README.md

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 # Universal Vocoder
 
+This is a restructured and rewritten version of [bshall/UniversalVocoding](https://github.com/bshall/UniversalVocoding).
 
 ### References
 
 - [Towards achieving robust universal neural vocoding](https://arxiv.org/abs/1811.06292)
-- [bshall/UniversalVocoding](https://github.com/bshall/UniversalVocoding)