Add a --help/-h flag to t/harness.
Add a --help/-h flag to t/harness.

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