eagerize combinations/permutations somewhat
eagerize combinations/permutations somewhat

Since we generally want all the combinations at a particular complexity
level, batch the gather/take at each level.  (Combinations over a range of
levels still are lazy on going to the next level.)  Runs about 25% faster.

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