[Global chat] Part1: UI for chat with unread messages

Past week we added chat into the videos, but we didn't add a way to check unread messages or be notified when somebody send a message in your chat.

@drag0s started working on this by adding a global chat that you can see all your videos and the messages sent. In this coding session I'm going to be working on the UI.

• Bootstrapping Global Chat: https://gitduck.com/watch/5da5e3f7951a393273f21c22
• UI Part 1: https://gitduck.com/watch/5da5f47d951a395269f21c27
• UI Part 2: https://gitduck.com/watch/5da61646951a398436f21c2c
• UI Part 3: https://gitduck.com/watch/5da63419951a390a16f21c30