stdlib: update comments and parameter names for startsWith() algorithm to clearly reflect semantics
stdlib: update comments and parameter names for startsWith() algorithm to
clearly reflect semantics

rdar://17567069


Swift SVN r19681

russbishop/swift,sdulal/swift,uasys/swift,manavgabhawala/swift,mightydeveloper/swift,adrfer/swift,jopamer/swift,tinysun212/swift-windows,CodaFi/swift,allevato/swift,emilstahl/swift,mightydeveloper/swift,jmgc/swift,milseman/swift,IngmarStein/swift,natecook1000/swift,kstaring/swift,modocache/swift,khizkhiz/swift,natecook1000/swift,xedin/swift,swiftix/swift,jopamer/swift,airspeedswift/swift,allevato/swift,MukeshKumarS/Swift,practicalswift/swift,nathawes/swift,therealbnut/swift,swiftix/swift.old,alblue/swift,ahoppen/swift,danielmartin/swift,modocache/swift,IngmarStein/swift,deyton/swift,uasys/swift,ken0nek/swift,devincoughlin/swift,kperryua/swift,shajrawi/swift,bitjammer/swift,jckarter/swift,kusl/swift,LeoShimonaka/swift,Ivacker/swift,djwbrown/swift,huonw/swift,return/swift,deyton/swift,frootloops/swift,slavapestov/swift,jckarter/swift,xedin/swift,danielmartin/swift,brentdax/swift,alblue/swift,nathawes/swift,therealbnut/swift,practicalswift/swift,jckarter/swift,nathawes/swift,kstaring/swift,return/swift,kusl/swift,danielmartin/swift,kperryua/swift,kperryua/swift,JaSpa/swift,alblue/swift,JGiola/swift,ben-ng/swift,OscarSwanros/swift,codestergit/swift,codestergit/swift,jopamer/swift,practicalswift/swift,CodaFi/swift,roambotics/swift,JGiola/swift,devincoughlin/swift,natecook1000/swift,jckarter/swift,harlanhaskins/swift,tjw/swift,gottesmm/swift,stephentyrone/swift,devincoughlin/swift,mightydeveloper/swift,lorentey/swift,nathawes/swift,kperryua/swift,modocache/swift,sdulal/swift,gregomni/swift,glessard/swift,milseman/swift,shahmishal/swift,karwa/swift,shajrawi/swift,dduan/swift,return/swift,gmilos/swift,cbrentharris/swift,gottesmm/swift,tkremenek/swift,emilstahl/swift,tjw/swift,zisko/swift,hughbe/swift,calebd/swift,xwu/swift,swiftix/swift,jtbandes/swift,apple/swift,frootloops/swift,roambotics/swift,zisko/swift,glessard/swift,tkremenek/swift,hughbe/swift,glessard/swift,therealbnut/swift,emilstahl/swift,MukeshKumarS/Swift,lorentey/swift,felix91gr/swift,benlangmuir/swift,jckarter/swift,codestergit/swift,arvedviehweger/swift,slavapestov/swift,MukeshKumarS/Swift,IngmarStein/swift,uasys/swift,tjw/swift,codestergit/swift,tardieu/swift,alblue/swift,jtbandes/swift,gmilos/swift,cbrentharris/swift,IngmarStein/swift,sdulal/swift,JaSpa/swift,harlanhaskins/swift,swiftix/swift.old,arvedviehweger/swift,bitjammer/swift,alblue/swift,khizkhiz/swift,cbrentharris/swift,modocache/swift,kusl/swift,LeoShimonaka/swift,jmgc/swift,frootloops/swift,zisko/swift,ahoppen/swift,huonw/swift,zisko/swift,kstaring/swift,KrishMunot/swift,jtbandes/swift,return/swift,modocache/swift,SwiftAndroid/swift,gottesmm/swift,alblue/swift,gregomni/swift,CodaFi/swift,ben-ng/swift,khizkhiz/swift,emilstahl/swift,Jnosh/swift,karwa/swift,kusl/swift,glessard/swift,swiftix/swift,ken0nek/swift,jmgc/swift,shajrawi/swift,swiftix/swift.old,SwiftAndroid/swift,kusl/swift,ahoppen/swift,tardieu/swift,sschiau/swift,sschiau/swift,slavapestov/swift,arvedviehweger/swift,devincoughlin/swift,ahoppen/swift,danielmartin/swift,gribozavr/swift,gribozavr/swift,Jnosh/swift,mightydeveloper/swift,jopamer/swift,kentya6/swift,tinysun212/swift-windows,kentya6/swift,jopamer/swift,stephentyrone/swift,xedin/swift,amraboelela/swift,therealbnut/swift,tjw/swift,CodaFi/swift,rudkx/swift,practicalswift/swift,LeoShimonaka/swift,CodaFi/swift,harlanhaskins/swift,deyton/swift,allevato/swift,manavgabhawala/swift,gottesmm/swift,gribozavr/swift,Jnosh/swift,SwiftAndroid/swift,zisko/swift,Ivacker/swift,SwiftAndroid/swift,tinysun212/swift-windows,apple/swift,kusl/swift,codestergit/swift,shajrawi/swift,therealbnut/swift,austinzheng/swift,amraboelela/swift,austinzheng/swift,tjw/swift,ken0nek/swift,cbrentharris/swift,slavapestov/swift,danielmartin/swift,sdulal/swift,frootloops/swift,kentya6/swift,MukeshKumarS/Swift,allevato/swift,calebd/swift,JGiola/swift,parkera/swift,atrick/swift,natecook1000/swift,deyton/swift,calebd/swift,atrick/swift,apple/swift,swiftix/swift.old,allevato/swift,Ivacker/swift,bitjammer/swift,gregomni/swift,parkera/swift,devincoughlin/swift,brentdax/swift,karwa/swift,parkera/swift,apple/swift,OscarSwanros/swift,shajrawi/swift,sschiau/swift,milseman/swift,frootloops/swift,harlanhaskins/swift,huonw/swift,xedin/swift,swiftix/swift.old,brentdax/swift,lorentey/swift,aschwaighofer/swift,LeoShimonaka/swift,practicalswift/swift,austinzheng/swift,gmilos/swift,MukeshKumarS/Swift,kusl/swift,bitjammer/swift,khizkhiz/swift,adrfer/swift,karwa/swift,hughbe/swift,ben-ng/swift,djwbrown/swift,tinysun212/swift-windows,jtbandes/swift,felix91gr/swift,aschwaighofer/swift,atrick/swift,nathawes/swift,swiftix/swift.old,emilstahl/swift,Jnosh/swift,kstaring/swift,sdulal/swift,rudkx/swift,felix91gr/swift,russbishop/swift,stephentyrone/swift,rudkx/swift,xwu/swift,LeoShimonaka/swift,IngmarStein/swift,gottesmm/swift,SwiftAndroid/swift,dduan/swift,JaSpa/swift,jckarter/swift,tjw/swift,hughbe/swift,jmgc/swift,arvedviehweger/swift,jckarter/swift,lorentey/swift,adrfer/swift,hooman/swift,stephentyrone/swift,kentya6/swift,arvedviehweg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