[stdlib] Add Substring comparison benchmarks
[stdlib] Add Substring comparison benchmarks

This reveals lots of unimplemented cases, which will cause us to uncomment the
disabled code.

stephentyrone/swift,rudkx/swift,allevato/swift,devincoughlin/swift,austinzheng/swift,devincoughlin/swift,jckarter/swift,xedin/swift,atrick/swift,apple/swift,jmgc/swift,atrick/swift,xwu/swift,karwa/swift,Jnosh/swift,milseman/swift,JGiola/swift,sschiau/swift,jtbandes/swift,rudkx/swift,shajrawi/swift,atrick/swift,gribozavr/swift,airspeedswift/swift,uasys/swift,rudkx/swift,atrick/swift,rudkx/swift,lorentey/swift,swiftix/swift,Jnosh/swift,benlangmuir/swift,glessard/swift,hooman/swift,lorentey/swift,airspeedswift/swift,ahoppen/swift,milseman/swift,shahmishal/swift,practicalswift/swift,amraboelela/swift,parkera/swift,hooman/swift,Jnosh/swift,xwu/swift,calebd/swift,CodaFi/swift,natecook1000/swift,xwu/swift,gribozavr/swift,karwa/swift,shahmishal/swift,glessard/swift,amraboelela/swift,practicalswift/swift,deyton/swift,Jnosh/swift,gribozavr/swift,danielmartin/swift,jmgc/swift,austinzheng/swift,tjw/swift,natecook1000/swift,practicalswift/swift,hughbe/swift,apple/swift,stephentyrone/swift,zisko/swift,roambotics/swift,huonw/swift,sschiau/swift,roambotics/swift,tjw/swift,tkremenek/swift,atrick/swift,JGiola/swift,swiftix/swift,sschiau/swift,calebd/swift,felix91gr/swift,nathawes/swift,benlangmuir/swift,harlanhaskins/swift,nathawes/swift,OscarSwanros/swift,lorentey/swift,OscarSwanros/swift,brentdax/swift,deyton/swift,gregomni/swift,amraboelela/swift,parkera/swift,deyton/swift,shahmishal/swift,shahmishal/swift,hughbe/swift,hooman/swift,jckarter/swift,felix91gr/swift,austinzheng/swift,frootloops/swift,JGiola/swift,djwbrown/swift,ahoppen/swift,jopamer/swift,OscarSwanros/swift,alblue/swift,jmgc/swift,jtbandes/swift,gregomni/swift,austinzheng/swift,ahoppen/swift,stephentyrone/swift,danielmartin/swift,nathawes/swift,benlangmuir/swift,shajrawi/swift,return/swift,felix91gr/swift,alblue/swift,huonw/swift,xedin/swift,ahoppen/swift,tkremenek/swift,deyton/swift,xedin/swift,JGiola/swift,jmgc/swift,stephentyrone/swift,glessard/swift,sschiau/swift,parkera/swift,roambotics/swift,hughbe/swift,practicalswift/swift,allevato/swift,gregomni/swift,jckarter/swift,uasys/swift,parkera/swift,huonw/swift,roambotics/swift,djwbrown/swift,zisko/swift,practicalswift/swift,huonw/swift,CodaFi/swift,shahmishal/swift,natecook1000/swift,apple/swift,danielmartin/swift,natecook1000/swift,hooman/swift,felix91gr/swift,tjw/swift,hooman/swift,uasys/swift,austinzheng/swift,deyton/swift,return/swift,brentdax/swift,sschiau/swift,milseman/swift,alblue/swift,brentdax/swift,brentdax/swift,nathawes/swift,gregomni/swift,amraboelela/swift,allevato/swift,hooman/swift,jtbandes/swift,karwa/swift,xedin/swift,gribozavr/swift,sschiau/swift,allevato/swift,glessard/swift,natecook1000/swift,jckarter/swift,jopamer/swift,tjw/swift,practicalswift/swift,parkera/swift,OscarSwanros/swift,karwa/swift,frootloops/swift,devincoughlin/swift,devincoughlin/swift,shahmishal/swift,gribozavr/swift,gregomni/swift,karwa/swift,harlanhaskins/swift,natecook1000/swift,jmgc/swift,shajrawi/swift,glessard/swift,xedin/swift,nathawes/swift,amraboelela/swift,gribozavr/swift,return/swift,gribozavr/swift,Jnosh/swift,CodaFi/swift,tkremenek/swift,atrick/swift,apple/swift,hooman/swift,benlangmuir/swift,parkera/swift,xwu/swift,jopamer/swift,zisko/swift,OscarSwanros/swift,sschiau/swift,benlangmuir/swift,CodaFi/swift,jmgc/swift,tkremenek/swift,calebd/swift,alblue/swift,allevato/swift,shajrawi/swift,JGiola/swift,aschwaighofer/swift,harlanhaskins/swift,calebd/swift,hughbe/swift,jckarter/swift,devincoughlin/swift,devincoughlin/swift,alblue/swift,alblue/swift,huonw/swift,karwa/swift,OscarSwanros/swift,jtbandes/swift,allevato/swift,hughbe/swift,deyton/swift,allevato/swift,jmgc/swift,return/swift,harlanhaskins/swift,aschwaighofer/swift,frootloops/swift,austinzheng/swift,alblue/swift,harlanhaskins/swift,jckarter/swift,return/swift,felix91gr/swift,swiftix/swift,tjw/swift,gregomni/swift,stephentyrone/swift,xwu/swift,deyton/swift,CodaFi/swift,apple/swift,danielmartin/swift,austinzheng/swift,airspeedswift/swift,jckarter/swift,lorentey/swift,jopamer/swift,jtbandes/swift,nathawes/swift,stephentyrone/swift,return/swift,practicalswift/swift,uasys/swift,amraboelela/swift,danielmartin/swift,roambotics/swift,jtbandes/swift,milseman/swift,devincoughlin/swift,Jnosh/swift,jtbandes/swift,xedin/swift,aschwaighofer/swift,djwbrown/swift,djwbrown/swift,aschwaighofer/swift,zisko/swift,tjw/swift,djwbrown/swift,shahmishal/swift,lorentey/swift,lorentey/swift,harlanhaskins/swift,swiftix/swift,frootloops/swift,swiftix/swift,frootloops/swift,natecook1000/swift,calebd/swift,amraboelela/swift,devincoughlin/swift,zisko/swift,jopamer/swift,nathawes/swift,tjw/swift,parkera/swift,parkera/swift,shajrawi/swift,xwu/swift,xedin/swift,benlangmuir/swift,airspeedswift/swift,Jnosh/swift,shajrawi/swift,aschwaighofer/swift,zisko/swift,uasys/swift,rudkx/swift,hughbe/swift,xedin/swift,milseman/swift,karwa/swift,tkremenek/swift,lorentey/swift,lorentey/swift,milseman/swift,danielmartin/swift,tkremenek/swift,rudkx/swift,felix91gr/swift,swiftix/swift,aschwaighofer/swift,hughbe/swift,frootloops/swift,return/swift,roambotics/swift,jopamer/swift,airspeedswift/swift,glessard/swift,huonw/swift,OscarSwanros/swift,harlanhaskins/swift,frootloops/swift,brentdax/swift,swiftix/swift,gribozavr/swift,felix91gr/swift,xwu/swift,uasys/swift,ahoppen/swift,shahmishal/swift,djwbrown/swift,apple/swift,uasys/swift,airspeedswift/swift,huonw/swift,calebd/swift,zisko/swift,ahoppen/swift,jopamer/swift,stephentyrone/swift,sschiau/swift,CodaFi/swift,airspeedswift/swift,shajrawi/swift,JGiola/swift,CodaFi/swift,aschwaighofer/swift,practicalswift/swift,shajrawi/swift,milseman/swift,brentdax/swift,djwbrown/swift,danielmartin/swift,calebd/swift,brentdax/swift,tkremenek/swift,karwa/swift