Fix problems with getMonotonicNSec on OS X
Fix problems with getMonotonicNSec on OS X

We were incorrectly multiplying by 1e9, which (a) meant we were
getting values that were far too large, and (b) meant that when
we casted from double to StgWord64 the result was 0, as the value
was out of range.

We now do all the work as StgWord64.

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