Update the description of 'assign'.
Update the description of 'assign'.

I also removed a restriction about the form of the operand that
doesn't seem to be enforced by SIL-gen at all.

Swift SVN r7951

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