Fix chdir and open. Use nqp::readfh and nqp::writefh
Fix chdir and open. Use nqp::readfh and nqp::writefh

rakudo/rakudo,cognominal/rakudo,rakudo/rakudo,lucasbuchala/rakudo,laben/rakudo,raydiak/rakudo,ab5tract/rakudo,niner/rakudo,tbrowder/rakudo,salortiz/rakudo,rakudo/rakudo,rakudo/rakudo,tony-o/rakudo,Leont/rakudo,skids/rakudo,nbrown/rakudo,paultcochrane/rakudo,dankogai/rakudo,labster/rakudo,jonathanstowe/rakudo,awwaiid/rakudo,laben/rakudo,samcv/rakudo,zostay/rakudo,tony-o/deb-rakudodaily,zhuomingliang/rakudo,softmoth/rakudo,Leont/rakudo,MasterDuke17/rakudo,awwaiid/rakudo,tony-o/rakudo,ugexe/rakudo,azawawi/rakudo,rakudo/rakudo,azawawi/rakudo,sjn/rakudo,dankogai/rakudo,skids/rakudo,retupmoca/rakudo,teodozjan/rakudo,raydiak/rakudo,Gnouc/rakudo,lucasbuchala/rakudo,skids/rakudo,lucasbuchala/rakudo,ab5tract/rakudo,MasterDuke17/rakudo,salortiz/rakudo,labster/rakudo,nbrown/rakudo,jonathanstowe/rakudo,tony-o/rakudo,Gnouc/rakudo,labster/rakudo,usev6/rakudo,tbrowder/rakudo,Gnouc/rakudo,b2gills/rakudo,samcv/rakudo,LLFourn/rakudo,LLFourn/rakudo,ungrim97/rakudo,b2gills/rakudo,sjn/rakudo,dankogai/rakudo,sergot/rakudo,tony-o/deb-rakudodaily,salortiz/rakudo,samcv/rakudo,Gnouc/rakudo,awwaiid/rakudo,Leont/rakudo,teodozjan/rakudo,Leont/rakudo,lucasbuchala/rakudo,skids/rakudo,labster/rakudo,sjn/rakudo,paultcochrane/rakudo,zostay/rakudo,sergot/rakudo,paultcochrane/rakudo,retupmoca/rakudo,MasterDuke17/rakudo,nbrown/rakudo,jonathanstowe/rakudo,zhuomingliang/rakudo,azawawi/rakudo,usev6/rakudo,b2gills/rakudo,zostay/rakudo,nunorc/rakudo,cygx/rakudo,nbrown/rakudo,nunorc/rakudo,labster/rakudo,teodozjan/rakudo,niner/rakudo,sergot/rakudo,tony-o/deb-rakudodaily,dwarring/rakudo,ungrim97/rakudo,tony-o/rakudo,samcv/rakudo,dwarring/rakudo,nbrown/rakudo,samcv/rakudo,jonathanstowe/rakudo,ab5tract/rakudo,tony-o/deb-rakudodaily,LLFourn/rakudo,ugexe/rakudo,salortiz/rakudo,nunorc/rakudo,ab5tract/rakudo,lucasbuchala/rakudo,ugexe/rakudo,tony-o/deb-rakudodaily,b2gills/rakudo,paultcochrane/rakudo,dwarring/rakudo,cognominal/rakudo,skids/rakudo,salortiz/rakudo,cygx/rakudo,dwarring/rakudo,MasterDuke17/rakudo,teodozjan/rakudo,zhuomingliang/rakudo,usev6/rakudo,usev6/rakudo,cygx/rakudo,labster/rakudo,cognominal/rakudo,sjn/rakudo,azawawi/rakudo,Gnouc/rakudo,ungrim97/rakudo,ungrim97/rakudo,Gnouc/rakudo,tbrowder/rakudo,sergot/rakudo,tony-o/rakudo,awwaiid/rakudo,zhuomingliang/rakudo,raydiak/rakudo,azawawi/rakudo,nbrown/rakudo,cygx/rakudo,jonathanstowe/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,ungrim97/rakudo,salortiz/rakudo,retupmoca/rakudo,usev6/rakudo,softmoth/rakudo,cognominal/rakudo,laben/rakudo,tony-o/deb-rakudodaily,tbrowder/rakudo,tony-o/rakudo,MasterDuke17/rakudo,nunorc/rakudo,softmoth/rakudo,dankogai/rakudo,tony-o/deb-rakudodaily,paultcochrane/rakudo,cygx/rakudo,laben/rakudo,awwaiid/rakudo,zostay/rakudo,retupmoca/rakudo,rakudo/rakudo,ugexe/rakudo,softmoth/rakudo,tbrowder/rakudo,dankogai/rakudo,niner/rakudo,LLFourn/rakudo,ugexe/rakudo,cognominal/rakudo,raydiak/rakudo,ab5tract/rakudo,niner/rakudo,b2gills/rakudo,LLFourn/rakudo,softmoth/rakudo,sjn/rakudo