Can’t wait until October 31 to parade around South Slope in a costume while consuming large quantities of alcohol? Barcrawls.com [http://barcrawls.com/] is here to help. Three South Slope Bars (Black Horse Pub [http://blackhorsebrooklyn.com/], Smith’s Tavern [http://www.yelp.com/biz/smiths-tavern-brooklyn-2] and The