chat: Add forward, rich editing and extra recipients: - There is a new "forward" menu in message. For now, a simple prompt ask for recipient JID. - A new "extra" menu is available next to input field. Inside there are 2 items for now: add extra recipient, and toggle rich edit mode. - Extra recipient option add a field to add an email-like "to", "cc" or "bcc" recipients. - Rich edit let use rich styling such as bold, italic, underline, etc. rel 461

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