[stdlib] Add missing comments
[stdlib] Add missing comments

Swift SVN r29720

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