Revert "[stdlib] Remove protocol availability annotations"
Revert "[stdlib] Remove protocol availability annotations"

I think I did this too early; it's supposed to be after Beta5.
This reverts r20348

Swift SVN r20350

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