Update README

[RodrigoEspinosa]

Update the README file to show an animation for the new GitterCLI layout for messages.

[rafiq33]

Please. Help me how can active. My bitcoin @wallet address.

[lucasjinreal]

How to send msg? I can display list but have to select and start a chat?

[RodrigoEspinosa]

Hi @jinfagang, this project has not received a lot of love lately (my fault), but the command to join is gitter-cli join <roomName> for example gitter-cli join gitterHQ/gitter.