paste: make MUCH faster and fix a couple bugs
paste: make MUCH faster and fix a couple bugs

steveklabnik/coreutils,dbrgn/coreutils,hexsel/coreutils,kwantam/coreutils,Shtong/coreutils,Shir0kamii/coreutils,dbrgn/coreutils,dbrgn/coreutils,Arcterus/coreutils,polapl/coreutils,jbcrail/coreutils,beni55/coreutils,kevgeniy/coreutils,Gianbaoluo/coreutils,Shtong/coreutils,dennis/coreutils,Gianbaoluo/coreutils,kevgeniy/coreutils,uutils/coreutils,dennis/coreutils,Shir0kamii/coreutils,silvio/rust-coreutils,tempbottle/coreutils,Heather/coreutils,wimh/coreutils,samfoo/coreutils,efuquen/coreutils,bundai223/coreutils,mauricio/coreutils,polapl/coreutils,mauricio/coreutils,efuquen/coreutils,uutils/coreutils,silvio/rust-coreutils,wimh/coreutils,sshling/coreutils,retep998/coreutils,jbcrail/coreutils,kball/coreutils,ebfe/coreutils,keunwoo/coreutils,keunwoo/coreutils,samfoo/coreutils,tempbottle/coreutils,bundai223/coreutils,steveklabnik/coreutils,Arcterus/coreutils,dokaptur/coreutils,kwantam/coreutils,sshling/coreutils,kball/coreutils,retep998/coreutils,beni55/coreutils,filmor/coreutils,ebfe/coreutils,hexsel/coreutils,uutils/coreutils,filmor/coreutils,Heather/coreutils