Add a text input box to allow chatting with the opponent

[programarivm]

After accepting an invitation to play chess with a friend, the players will probably want to have a chat with each other. Thus, an input text box should be added to the UI for this purpose just below the Invited friend board, as it is shown in the GIF below.

Figure 1. A text input box to allow chatting with the opponent should appear below the Invited friend board.

No additional programming is required to close this issue — just add a text input box, it's a really good first issue to get familiar with the codebase! It is intended to install and set up the testing-redux-chess app in your computer in order to solve more issues.

Keep it up, and happy coding and learning.