Bring back nickname weight system.

Was removed during development to test a fix against a bug that thought might be related to it. Forgot to ever put it back.
Added work to NSStringHelper.m
Append a whitespace after nickname in log file if there is not one already there.
Insert headers into log files to indicate beginning and end of sessions.
Handle (Max SendQ exceeded) disconnects.
If away-notify is available, WHO on join.
Optimization.

Reload only items that need reloading when states change instead of reloading the entire server list for every small action.