Previously, the bot wouldn't address people by nick if the provided nick
argument doesn't exist in the channel.
Now, the bot's nick list is searched for a nick with a certain similarity
percentage in the order of most recently spoken nicks first. This allows
the bot to address nicks when somebody may have forgotten to add a trailing
underscore/punctuation or may have typoed the nick.
The similarity percentage can be set via the interpreter->nick_similiarty
registry key. A value of 0 should disable the behavior.
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