Rewrite of List.(uniq|squish) using map()
Rewrite of List.(uniq|squish) using map()

For "my @a=1..100000; my @b= @a.(uniq|squish) the improvements were:
  uniq:   CPU from 0m23.214s to 0m10.107s  (aka 56% less CPU)
  squish: CPU from 0m10.911s to 0m7.790s   (aka 28% less CPU)

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