Improved language in the Readme

[junichi11]

@JudeRosario Sorry, my explanation was bad. At first, I want you to checkout the nb80dev branch, then

• change something
• commit your changes
• send your PR to nb80dev

because current development branch is nb80dev.

Could you do that?

[JudeRosario]

OMG .. I've just realized what I've done. Sorry. Dint realize it was the dev branch. Will send a new PR soon ..