2.0.0

• new message type polls
• new emoticons
• central message center for open conversations
• only show last 20 messages
• reduce scroll speed
• save last window size and position on application restart
• new configuration parameter for welcome text on application start
• update all dependencies and switch to nw.js and io.js
• set correct logo icon in header
• fix unread counter bug
• ignore messages sent to a room a user has left