install.sh: use portable printf instead of echo
install.sh: use portable printf instead of echo

FrankSansC/oh-my-zsh,nunogt/oh-my-zsh,FrankSansC/oh-my-zsh,FrankSansC/oh-my-zsh,FrankSansC/oh-my-zsh,nunogt/oh-my-zsh,tekniklr/oh-my-zsh,tekniklr/oh-my-zsh