Re-word and fix AudioKit Core README
Re-word and fix AudioKit Core README

audiokit/AudioKit,eljeff/AudioKit,adamnemecek/AudioKit,audiokit/AudioKit,eljeff/AudioKit,adamnemecek/AudioKit,eljeff/AudioKit,audiokit/AudioKit,adamnemecek/AudioKit,eljeff/AudioKit,audiokit/AudioKit,adamnemecek/AudioKit