GUI: add table/tourney chat to deck editor for draft/sideboard/construct

[JayDi85]

Current table/tourney chat is useless:

• waiting table chat hides on match/tourney started;
• tourney chat in another window/panel and users don't want to switch to it;

XMage chat engine supports multiple rooms (game, tourney, server lobby, etc). And it supports multiple clients (viewers) for same room too.

So the main idea:

• must have 3 shared chats for server lobby, table (same as tourney and waiting), match (same as game);
• history of chat messages must be restored after reconnect (Save chat history on server and client sides #5562);
• must support multiple instances of the same chat;
• deck editor must show table chat;
• optional: show game and table chats in the same window (its can be hard to implement cause there are some keyboard/hotkeys code and other chat related lifehacks);
• optional: add private messages (looks like a popup chat window for private messages between users). Xmage has whisper feature, but it hard to use (must send chat message with username to make it private).