Update access control proposal based on today's discussion.
Update access control proposal based on today's discussion.

Also add a section on "Non-Goals: 'class-only' and 'protected'".

Swift SVN r18965

Ivacker/swift,swiftix/swift.old,xwu/swift,brentdax/swift,milseman/swift,airspeedswift/swift,sschiau/swift,karwa/swift,felix91gr/swift,kstaring/swift,amraboelela/swift,uasys/swift,apple/swift,LeoShimonaka/swift,shajrawi/swift,sdulal/swift,glessard/swift,huonw/swift,dduan/swift,rudkx/swift,deyton/swift,tjw/swift,lorentey/swift,IngmarStein/swift,atrick/swift,sschiau/swift,slavapestov/swift,modocache/swift,swiftix/swift.old,djwbrown/swift,MukeshKumarS/Swift,roambotics/swift,swiftix/swift.old,swiftix/swift.old,milseman/swift,jckarter/swift,danielmartin/swift,Ivacker/swift,KrishMunot/swift,xwu/swift,Ivacker/swift,kperryua/swift,jmgc/swift,JGiola/swift,calebd/swift,lorentey/swift,danielmartin/swift,nathawes/swift,khizkhiz/swift,allevato/swift,jmgc/swift,nathawes/swift,jckarter/swift,aschwaighofer/swift,OscarSwanros/swift,KrishMunot/swift,cbrentharris/swift,therealbnut/swift,manavgabhawala/swift,Jnosh/swift,dduan/swift,MukeshKumarS/Swift,swiftix/swift,huonw/swift,johnno1962d/swift,kstaring/swift,parkera/swift,gmilos/swift,Jnosh/swift,hughbe/swift,airspeedswift/swift,apple/swift,gribozavr/swift,felix91gr/swift,sdulal/swift,russbishop/swift,practicalswift/swift,kusl/swift,uasys/swift,khizkhiz/swift,shajrawi/swift,calebd/swift,hooman/swift,sdulal/swift,ben-ng/swift,kstaring/swift,codestergit/swift,kstaring/swift,milseman/swift,bitjammer/swift,lorentey/swift,tkremenek/swift,therealbnut/swift,djwbrown/swift,uasys/swift,tjw/swift,allevato/swift,aschwaighofer/swift,tinysun212/swift-windows,zisko/swift,tinysun212/swift-windows,JaSpa/swift,ben-ng/swift,jmgc/swift,calebd/swift,danielmartin/swift,hughbe/swift,manavgabhawala/swift,devincoughlin/swift,felix91gr/swift,hooman/swift,natecook1000/swift,devincoughlin/swift,parkera/swift,LeoShimonaka/swift,xedin/swift,danielmartin/swift,uasys/swift,gottesmm/swift,KrishMunot/swift,sschiau/swift,ken0nek/swift,Ivacker/swift,jtbandes/swift,russbishop/swift,KrishMunot/swift,cbrentharris/swift,JGiola/swift,roambotics/swift,brentdax/swift,tkremenek/swift,khizkhiz/swift,kperryua/swift,swiftix/swift.old,felix91gr/swift,airspeedswift/swift,bitjammer/swift,glessard/swift,stephentyrone/swift,dreamsxin/swift,natecook1000/swift,danielmartin/swift,swiftix/swift,ken0nek/swift,kusl/swift,jopamer/swift,lorentey/swift,kstaring/swift,jmgc/swift,CodaFi/swift,zisko/swift,tardieu/swift,mightydeveloper/swift,parkera/swift,allevato/swift,dduan/swift,jmgc/swift,emilstahl/swift,kentya6/swift,therealbnut/swift,tardieu/swift,mightydeveloper/swift,gribozavr/swift,shajrawi/swift,xedin/swift,shajrawi/swift,JaSpa/swift,brentdax/swift,gribozavr/swift,kstaring/swift,deyton/swift,hughbe/swift,parkera/swift,deyton/swift,karwa/swift,calebd/swift,ahoppen/swift,tinysun212/swift-windows,atrick/swift,stephentyrone/swift,kentya6/swift,codestergit/swift,jtbandes/swift,airspeedswift/swift,LeoShimonaka/swift,adrfer/swift,devincoughlin/swift,gribozavr/swift,LeoShimonaka/swift,modocache/swift,emilstahl/swift,jmgc/swift,SwiftAndroid/swift,amraboelela/swift,cbrentharris/swift,devincoughlin/swift,johnno1962d/swift,lorentey/swift,atrick/swift,alblue/swift,apple/swift,gregomni/swift,OscarSwanros/swift,codestergit/swift,stephentyrone/swift,sdulal/swift,johnno1962d/swift,karwa/swift,frootloops/swift,mightydeveloper/swift,tkremenek/swift,modocache/swift,huonw/swift,Jnosh/swift,jopamer/swift,jtbandes/swift,frootloops/swift,Ivacker/swift,lorentey/swift,felix91gr/swift,allevato/swift,karwa/swift,harlanhaskins/swift,JGiola/swift,shahmishal/swift,cbrentharris/swift,roambotics/swift,jopamer/swift,KrishMunot/swift,tinysun212/swift-windows,devincoughlin/swift,tjw/swift,CodaFi/swift,xedin/swift,JGiola/swift,djwbrown/swift,jckarter/swift,airspeedswift/swift,arvedviehweger/swift,gribozavr/swift,devincoughlin/swift,hooman/swift,gmilos/swift,apple/swift,return/swift,bitjammer/swift,cbrentharris/swift,ben-ng/swift,gregomni/swift,jmgc/swift,swiftix/swift,alblue/swift,xwu/swift,atrick/swift,ben-ng/swift,manavgabhawala/swift,jckarter/swift,hooman/swift,huonw/swift,gottesmm/swift,djwbrown/swift,glessard/swift,sschiau/swift,tjw/swift,uasys/swift,cbrentharris/swift,hooman/swift,slavapestov/swift,jopamer/swift,roambotics/swift,parkera/swift,calebd/swift,natecook1000/swift,ben-ng/swift,nathawes/swift,tardieu/swift,frootloops/swift,swiftix/swift,MukeshKumarS/Swift,slavapestov/swift,bitjammer/swift,CodaFi/swift,kusl/swift,gottesmm/swift,stephentyrone/swift,MukeshKumarS/Swift,karwa/swift,JaSpa/swift,Jnosh/swift,gregomni/swift,emilstahl/swift,benlangmuir/swift,felix91gr/swift,calebd/swift,kperryua/swift,tkremenek/swift,sdulal/swift,karwa/swift,zisko/swift,JGiola/swift,lorentey/swift,gottesmm/swift,milseman/swift,gottesmm/swift,JaSpa/swift,gottesmm/swift,austinzheng/swift,harlanhaskins/swift,brentdax/swift,cbrentharris/swift,IngmarStein/swift,ahoppen/swift,IngmarStein/swift,tinysun212/swift-windows,aschwaighofer/swift,OscarSwanros/swift,therealbnut/swift,dduan/swift,atrick/swift,glessard/swift,adrfer/swift,tjw/swift,gregomni/swift,johnno1962d/swift,amraboelela/swift,swiftix/swift.old,amraboelela/swift,JaSpa/swift,parkera/swift,jopamer/swift,uasys/swift,tjw/swift,nathawes/swift,lorentey/swift,milseman/swift,apple/swift,harlanhaskins/swift,dreamsxin/swift,ken0nek/swift,ken0nek/swift,khizkhiz/swift,Jnosh/swift,adrfer/swift,parkera/swift,xwu/swift,MukeshKumarS/Swift,natecook1000/swift,harlanhaskins/swift,Ivacker/swift,JGiola/swift,ahoppen/swift,johnno1962d/swift,tkremenek/swift,russbishop/swift,gribozavr/swift,kperryua/swift,CodaFi/swift,LeoShimonaka/swift,glessard/swift,ken0nek/swift,benlangmuir/swift,arvedviehweger/swift,huonw/swift,mightydeveloper/swift,emilstahl/swift,roambotics/swift,codestergit/swift,practicalswift/swift,russbishop/swift,kperryua/swift,slavapestov/swift,practicalswift/swift,johnno1962d/swift,adrfer/swift,atrick/swift,jckarter/swift,shahmishal/swift,shajrawi/swift,khizkhiz/swift,kusl/swift,SwiftAndroid/swift,nathawes/swift,IngmarStein/swift,swiftix/swift,JaSpa/swift,dduan/swift,adrfer/swift,kentya6/swift,jckarter/swift,tkremenek/swift,codestergit/swift,OscarSwanros/swift,hughbe/swift,modocache/swift,return/swift,russbishop/swift,modocache/swift,shahmishal/swift,benlangmuir/swift,frootloops/swift,gribozavr/swift,adrfer/swift,zisko/swift,sdulal/swift,frootloops/swift,khizkhiz/swift,return/swift,airspeedswift/swift,gregomni/swift,zisko/swift,tardieu/swift,alblue/swift,jtbandes/swift,slavapestov/swift,cbrentharris/swift,return/swift,benlangmuir/swift,SwiftAndroid/swift,arvedviehweger/swift,kentya6/swift,shahmishal/swift,allevato/swift,aschwaighofer/swift,karwa/swift,ahoppen/swift,tardieu/swift,therealbnut/swift,austinzheng/swift,shahmishal/swift,deyton/swift,KrishMunot/swift,apple/swift,therealbnut/swift,ahoppen/swift,return/swift,arvedviehweger/swift,amraboelela/swift,frootloops/swift,alblue/swift,calebd/swift,harlanhaskins/swift,johnno1962d/swift,alblue/swift,rudkx/swift,allevato/swift,kentya6/swift,tardieu/swift,jtbandes/swift,hughbe/swift,aschwaighofer/swift,russbishop/swift,return/swift,deyton/swift,manavgabhawala/swift,SwiftAndroid/swift,modocache/swift,tinysun212/swift-windows,tkremenek/swift,deyton/swift,jtbandes/swift,kperryua/swift,ken0nek/swift,IngmarStein/swift,kentya6/swift,hooman/swift,SwiftAndroid/swift,austinzheng/swift,gmilos/swift,jopamer/swift,nathawes/swift,emilstahl/swift,arvedviehweger/swift,KrishMunot/swift,xedin/swift,tjw/swift,gregomni/swift,frootloops/swift,LeoShimonaka/swift,uasys/swift,gmilos/swift,SwiftAndroid/swift,IngmarStein/swift,stephentyrone/swift,bitjammer/swift,slavapestov/swift,brentdax/swift,xwu/swift,zisko/swift,deyton/swift,gribozavr/swift,danielmartin/swift,xwu/swift,kentya6/swift,bitjammer/swift,dduan/swift,harlanhaskins/swift,hughbe/swift,practicalswift/swift,sdulal/swift,practicalswift/swift,xwu/swift,harlanhaskins/swift,hughbe/swift,benlangmuir/swift,sschiau/swift,amraboelela/swift,rudkx/swift,devincoughlin/swift,djwbrown/swift,sdulal/swift,Ivacker/swift,mightydeveloper/swift,tinysun212/swift-windows,parkera/swift,CodaFi/swift,felix91gr/swift,kusl/swift,arvedviehweger/swift,zisko/swift,OscarSwanros/swift,gmilos/swift,kusl/swift,danielmartin/swift,CodaFi/swift,austinzheng/swift,huonw/swift,return/swift,shajrawi/swift,rudkx/swift,JaSpa/swift,ben-ng/swift,natecook1000/swift,Jnosh/swift,karwa/swift,benlangmuir/swift,shajrawi/swift,ben-ng/swift,modocache/swift,IngmarStein/swift,allevato/swift,huonw/swift,xedin/swift,CodaFi/swift,kusl/swift,stephentyrone/swift,therealbnut/swift,devincoughlin/swift,djwbrown/swift,aschwaighofer/swift,ken0nek/swift,Jnosh/swift,bitjammer/swift,xedin/swift,jckarter/swift,sschiau/swift,natecook1000/swift,roambotics/swift,kstaring/swift,xedin/swift,mightydeveloper/swift,shahmishal/swift,milseman/swift,emilstahl/swift,swiftix/swift.old,ahoppen/swift,sschiau/swift,swiftix/swift.old,LeoShimonaka/swift,xedin/swift,alblue/swift,gmilos/swift,sschiau/swift,mightydeveloper/swift,codestergit/swift,khizkhiz/swift,kusl/swift,practicalswift/swift,airspeedswift/swift,SwiftAndroid/swift,emilstahl/swift,manavgabhawala/swift,nathawes/swift,MukeshKumarS/Swift,shahmishal/swift,OscarSwanros/swift,mightydeveloper/swift,practicalswift/swift,dduan/swift,stephentyrone/swift,austinzheng/swift,rudkx/swift,amraboelela/swift,jopamer/swift,codestergit/swift,arvedviehweger/swift,alblue/swift,shahmishal/swift,gmilos/swift,hooman/swift,russbishop/swift,slavapestov/swift,swiftix/swift,tardieu/swift,djwbrown/swift,natecook1000/swift,Ivacker/swift,swiftix/swift,emilstahl/swift,austinzheng/swift,brentdax/swift,brentdax/swift,gottesmm/swift,kperryua/swift,adrfer/swift,manavgabhawala/swift,rudkx/swift,kentya6/swift,glessard/swift,austinzheng/swift,jtbandes/swift,LeoShimonaka/swift,practicalswift/swift,aschwaighofer/swift,manavgabhawala/swift,MukeshKumarS/Swift,shajrawi/swift,milseman/swift,OscarSwanros/swift