Mention that the user has to import GHC.Exts for Constraint
Mention that the user has to import GHC.Exts for Constraint

(required judging from confusion on #haskell right now.)

snoyberg/ghc,olsner/ghc,frantisekfarka/ghc-dsi,siddhanathan/ghc,olsner/ghc,gridaphobe/ghc,lukexi/ghc,olsner/ghc,mettekou/ghc,forked-upstream-packages-for-ghcjs/ghc,TomMD/ghc,hferreiro/replay,forked-upstream-packages-for-ghcjs/ghc,vikraman/ghc,sgillespie/ghc,GaloisInc/halvm-ghc,anton-dessiatov/ghc,urbanslug/ghc,forked-upstream-packages-for-ghcjs/ghc,AlexanderPankiv/ghc,wxwxwwxxx/ghc,gridaphobe/ghc,tibbe/ghc,urbanslug/ghc,hferreiro/replay,christiaanb/ghc,wxwxwwxxx/ghc,ezyang/ghc,GaloisInc/halvm-ghc,AlexanderPankiv/ghc,bitemyapp/ghc,shlevy/ghc,frantisekfarka/ghc-dsi,ml9951/ghc,ezyang/ghc,lukexi/ghc,ryantm/ghc,oldmanmike/ghc,nushio3/ghc,hferreiro/replay,ezyang/ghc,sdiehl/ghc,oldmanmike/ghc,snoyberg/ghc,vTurbine/ghc,sdiehl/ghc,nushio3/ghc,green-haskell/ghc,AlexanderPankiv/ghc,acowley/ghc,elieux/ghc,mfine/ghc,fmthoma/ghc,acowley/ghc,ml9951/ghc,ryantm/ghc,mcschroeder/ghc,nathyong/microghc-ghc,mettekou/ghc,spacekitteh/smcghc,TomMD/ghc,siddhanathan/ghc,holzensp/ghc,oldmanmike/ghc,AlexanderPankiv/ghc,sdiehl/ghc,TomMD/ghc,wxwxwwxxx/ghc,gcampax/ghc,hferreiro/replay,shlevy/ghc,elieux/ghc,jstolarek/ghc,vTurbine/ghc,holzensp/ghc,nkaretnikov/ghc,green-haskell/ghc,siddhanathan/ghc,gcampax/ghc,ezyang/ghc,olsner/ghc,christiaanb/ghc,nkaretnikov/ghc,oldmanmike/ghc,christiaanb/ghc,tjakway/ghcjvm,gcampax/ghc,tjakway/ghcjvm,fmthoma/ghc,ghc-android/ghc,mettekou/ghc,spacekitteh/smcghc,forked-upstream-packages-for-ghcjs/ghc,christiaanb/ghc,shlevy/ghc,nkaretnikov/ghc,ml9951/ghc,da-x/ghc,vikraman/ghc,sgillespie/ghc,frantisekfarka/ghc-dsi,elieux/ghc,ml9951/ghc,vTurbine/ghc,shlevy/ghc,bitemyapp/ghc,gcampax/ghc,ryantm/ghc,snoyberg/ghc,gcampax/ghc,elieux/ghc,TomMD/ghc,fmthoma/ghc,nathyong/microghc-ghc,da-x/ghc,forked-upstream-packages-for-ghcjs/ghc,mcschroeder/ghc,ml9951/ghc,mfine/ghc,tjakway/ghcjvm,wxwxwwxxx/ghc,fmthoma/ghc,jstolarek/ghc,mettekou/ghc,anton-dessiatov/ghc,hferreiro/replay,holzensp/ghc,shlevy/ghc,spacekitteh/smcghc,mfine/ghc,hferreiro/replay,AlexanderPankiv/ghc,frantisekfarka/ghc-dsi,elieux/ghc,siddhanathan/ghc,holzensp/ghc,GaloisInc/halvm-ghc,mfine/ghc,snoyberg/ghc,vTurbine/ghc,mettekou/ghc,ghc-android/ghc,shlevy/ghc,christiaanb/ghc,siddhanathan/ghc,green-haskell/ghc,elieux/ghc,ryantm/ghc,vTurbine/ghc,nushio3/ghc,urbanslug/ghc,urbanslug/ghc,AlexanderPankiv/ghc,snoyberg/ghc,tibbe/ghc,siddhanathan/ghc,vikraman/ghc,tjakway/ghcjvm,lukexi/ghc,mfine/ghc,holzensp/ghc,nushio3/ghc,fmthoma/ghc,shlevy/ghc,jstolarek/ghc,sdiehl/ghc,olsner/ghc,bitemyapp/ghc,bitemyapp/ghc,acowley/ghc,ryantm/ghc,anton-dessiatov/ghc,wxwxwwxxx/ghc,ghc-android/ghc,AlexanderPankiv/ghc,sdiehl/ghc,urbanslug/ghc,GaloisInc/halvm-ghc,spacekitteh/smcghc,jstolarek/ghc,ghc-android/ghc,lukexi/ghc-7.8-arm64,tjakway/ghcjvm,ezyang/ghc,nkaretnikov/ghc,sgillespie/ghc,ml9951/ghc,tibbe/ghc,ghc-android/ghc,oldmanmike/ghc,tjakway/ghcjvm,green-haskell/ghc,fmthoma/ghc,siddhanathan/ghc,frantisekfarka/ghc-dsi,urbanslug/ghc,tibbe/ghc,oldmanmike/ghc,wxwxwwxxx/ghc,sgillespie/ghc,spacekitteh/smcghc,vTurbine/ghc,lukexi/ghc-7.8-arm64,lukexi/ghc-7.8-arm64,ml9951/ghc,nathyong/microghc-ghc,mfine/ghc,acowley/ghc,mfine/ghc,anton-dessiatov/ghc,jstolarek/ghc,lukexi/ghc,sdiehl/ghc,acowley/ghc,sgillespie/ghc,ghc-android/ghc,gridaphobe/ghc,ezyang/ghc,gridaphobe/ghc,nathyong/microghc-ghc,lukexi/ghc,acowley/ghc,christiaanb/ghc,elieux/ghc,da-x/ghc,nushio3/ghc,anton-dessiatov/ghc,da-x/ghc,tjakway/ghcjvm,vikraman/ghc,nathyong/microghc-ghc,TomMD/ghc,GaloisInc/halvm-ghc,nkaretnikov/ghc,snoyberg/ghc,mcschroeder/ghc,wxwxwwxxx/ghc,mcschroeder/ghc,green-haskell/ghc,GaloisInc/halvm-ghc,forked-upstream-packages-for-ghcjs/ghc,gcampax/ghc,TomMD/ghc,nushio3/ghc,acowley/ghc,anton-dessiatov/ghc,nkaretnikov/ghc,ghc-android/ghc,TomMD/ghc,sdiehl/ghc,da-x/ghc,sgillespie/ghc,gridaphobe/ghc,vTurbine/ghc,nathyong/microghc-ghc,sgillespie/ghc,da-x/ghc,mettekou/ghc,lukexi/ghc-7.8-arm64,nathyong/microghc-ghc,da-x/ghc,vikraman/ghc,bitemyapp/ghc,fmthoma/ghc,gridaphobe/ghc,urbanslug/ghc,christiaanb/ghc,ml9951/ghc,ezyang/ghc,mettekou/ghc,oldmanmike/ghc,vikraman/ghc,tibbe/ghc,olsner/ghc,nushio3/ghc,GaloisInc/halvm-ghc,mcschroeder/ghc,mcschroeder/ghc,anton-dessiatov/ghc,forked-upstream-packages-for-ghcjs/ghc,hferreiro/replay,gcampax/ghc,vikraman/ghc,olsner/ghc,nkaretnikov/ghc,snoyberg/ghc,lukexi/ghc-7.8-arm64,gridaphobe/ghc,mcschroeder/ghc