Isy's Archery Addition

I've posted this earlier today on the forums http://smf.cataclysmdda.com/index.php?topic=1750.0 but Williham pointed out to me that I should be using github. All changes made ,as can be seen, are additions. However the balancing of the items added should be reconsidered in my opinion. (please see the forum post and corresponding edits.txt file)