IrcBridgeImprovements

This contains suggestions and drafts for the blueprint https://blueprints.launchpad.net/widelands/+spec/optimize-irc-bridge

Implementation requires both code changes to the Widelands Metaserver and Widelands

• Introduce a fourth type of user (beside admin and (un)registered) of type IRC or CHAT.
• The IRC bridge maintains these users on join/quit
• Add new icon for these in the lobby
• Add new button "Hide IRC users" in Lobby to allow hiding all IRC users and stop getting messages from IRC

Unsorted blurps of thoughts:

• I suggest this blueprint should also have a forum link for discussion.
• in IRC it is pretty annoying to get information about each entering or leaving user in the lobby. Opening games is more interesting.
• It seems excessive to send each chat message from IRC to the metaserver. Maybe only messages to the bridge itself (i.e. private messages or strings starting with ircbride: or so) should be send. Discoverability for the users then becomes an issue.
• querying the bridge for the userlist on the metaserver would be nice too.