feat: enable relative line numbers in vim

templates/etc/vim/vimrc.local.j2

 set encoding=utf-8
 syntax on
-set number      " display line numberset number
+set number relativenumber      " display line numberset number
 set hlsearch    " highlight all search results
 set ignorecase  " do case insensitive search
 set incsearch   " show incremental search results as you type