Update README.md (#23760)
Update README.md (#23760)

beautified Readme , removed bullet
Hixie/flutter,cbracken/flutter,Hixie/flutter,tvolkert/flutter,cbracken/flutter,cbracken/flutter,flutter/flutter,tvolkert/flutter,cbracken/flutter,tvolkert/flutter,tvolkert/flutter,tvolkert/flutter,tvolkert/flutter,flutter/flutter,cbracken/flutter,flutter/flutter,flutter/flutter,Hixie/flutter,Hixie/flutter,flutter/flutter,Hixie/flutter,Hixie/flutter,tvolkert/flutter,flutter/flutter,cbracken/flutter,Hixie/flutter,Hixie/flutter,cbracken/flutter,flutter/flutter,tvolkert/flutter,tvolkert/flutter,flutter/flutter,Hixie/flutter,cbracken/flutter,cbracken/flutter,flutter/flutter,tvolkert/flutter,cbracken/flutter,Hixie/flutter,flutter/flutter