[semantic-arc] Rename isConsumed -> isDeadLiveRange.
[semantic-arc] Rename isConsumed -> isDeadLiveRange.

Also, eliminate some bitrot from comments.

jckarter/swift,jckarter/swift,benlangmuir/swift,gregomni/swift,tkremenek/swift,apple/swift,rudkx/swift,apple/swift,harlanhaskins/swift,gribozavr/swift,jckarter/swift,tkremenek/swift,aschwaighofer/swift,hooman/swift,hooman/swift,sschiau/swift,devincoughlin/swift,benlangmuir/swift,harlanhaskins/swift,JGiola/swift,airspeedswift/swift,apple/swift,xwu/swift,jmgc/swift,airspeedswift/swift,tkremenek/swift,gregomni/swift,gregomni/swift,nathawes/swift,xwu/swift,harlanhaskins/swift,harlanhaskins/swift,allevato/swift,lorentey/swift,nathawes/swift,harlanhaskins/swift,parkera/swift,CodaFi/swift,apple/swift,gribozavr/swift,nathawes/swift,aschwaighofer/swift,jckarter/swift,ahoppen/swift,airspeedswift/swift,xwu/swift,xwu/swift,glessard/swift,parkera/swift,gregomni/swift,sschiau/swift,allevato/swift,hooman/swift,lorentey/swift,atrick/swift,karwa/swift,devincoughlin/swift,gribozavr/swift,nathawes/swift,benlangmuir/swift,sschiau/swift,stephentyrone/swift,rudkx/swift,jmgc/swift,jmgc/swift,xwu/swift,glessard/swift,parkera/swift,tkremenek/swift,devincoughlin/swift,xwu/swift,tkremenek/swift,gribozavr/swift,atrick/swift,hooman/swift,lorentey/swift,karwa/swift,rudkx/swift,harlanhaskins/swift,karwa/swift,xwu/swift,gribozavr/swift,roambotics/swift,rudkx/swift,rudkx/swift,gregomni/swift,devincoughlin/swift,parkera/swift,atrick/swift,gribozavr/swift,roambotics/swift,nathawes/swift,sschiau/swift,lorentey/swift,atrick/swift,ahoppen/swift,stephentyrone/swift,aschwaighofer/swift,glessard/swift,benlangmuir/swift,karwa/swift,roambotics/swift,jmgc/swift,parkera/swift,atrick/swift,aschwaighofer/swift,harlanhaskins/swift,nathawes/swift,apple/swift,aschwaighofer/swift,allevato/swift,nathawes/swift,jmgc/swift,jckarter/swift,ahoppen/swift,karwa/swift,benlangmuir/swift,parkera/swift,hooman/swift,karwa/swift,rudkx/swift,allevato/swift,lorentey/swift,roambotics/swift,sschiau/swift,benlangmuir/swift,tkremenek/swift,jmgc/swift,sschiau/swift,CodaFi/swift,allevato/swift,glessard/swift,tkremenek/swift,lorentey/swift,CodaFi/swift,hooman/swift,stephentyrone/swift,JGiola/swift,lorentey/swift,devincoughlin/swift,devincoughlin/swift,gribozavr/swift,glessard/swift,jmgc/swift,lorentey/swift,karwa/swift,sschiau/swift,apple/swift,stephentyrone/swift,atrick/swift,airspeedswift/swift,parkera/swift,JGiola/swift,jckarter/swift,airspeedswift/swift,airspeedswift/swift,gregomni/swift,devincoughlin/swift,allevato/swift,CodaFi/swift,ahoppen/swift,hooman/swift,JGiola/swift,stephentyrone/swift,devincoughlin/swift,aschwaighofer/swift,roambotics/swift,CodaFi/swift,aschwaighofer/swift,glessard/swift,sschiau/swift,stephentyrone/swift,gribozavr/swift,roambotics/swift,stephentyrone/swift,ahoppen/swift,CodaFi/swift,CodaFi/swift,JGiola/swift,JGiola/swift,airspeedswift/swift,allevato/swift,parkera/swift,karwa/swift,jckarter/swift,ahoppen/swift