Update old style callbacks for chatFromLogFile functions to lambdas
Keep track of people's log's name using their IDs, but don't rename.
Fallback on ID if name is empty (if the grid is a meanie)
Also track group names this way, sometimes those change.
Prefer std::array, since we're in the area.
Fairly certain this adds the feature in which the user may click the online notification to open a chat with the user coming online.
Translators may want to look at the xml changes of this change to see what to update
Removes old LegacyMultiAttachmentSupport patch
Moves LLAvatarName-centric functions into LLAvatarName from elsewhere.
Adds boost::signals2::connections to name polling places.
Removes more old icky static callbacks
Merge from Alchemy, credit where due~
Update notifications.xml to have a bunch of the tags from upstream to ease diffing
