Update README.md with contribution information

Julien LepillerThu Apr 18 14:25:39+0200 2019

54b501d

nani/app/furiganatextview/src/test/java
namelast commitdate
eu/Add furiganaMon Apr 15 20:09:48+0200 2019
se/Add furiganaMon Apr 15 20:09:48+0200 2019