Implement a better way to chat with in-game players using the frontend

[Inei1]

Right now, it is possible to use the frontend to chat with players in-game using the console tab. The say and whisper commands can be used to send a message, and the console receives chat messages normally. However, this is a bit cumbersome, as having to type say before every message is annoying, and the console is going to be filled with other, non-chat related messages.

Since chatting is such a central feature, a new tab should be added that provides a convenient interface for chatting. This new tab could use code similar to the console to send and receive commands, with a filter to only show CHAT console messages (see the Message interface). Sending a chat message should only involve prepending say with a space to the message before sending it like normal.