Remove trailing whitespace from files on save

vim/vimrc

@@ -247,6 +247,21 @@ set directory=~/.vim/backup
 " better way to run this?
 let ignorethisvar = system("mkdir -p ~/.vim/backup")
 
+" Strip trailing whitespace
+function! <SID>StripTrailingWhitespaces()
+    " Preparation: save last search, and cursor position.
+    let _s=@/
+    let l = line(".")
+    let c = col(".")
+    " Do the business:
+    %s/\s\+$//e
+    " Clean up: restore previous search history, and cursor position
+    let @/=_s
+    call cursor(l, c)
+endfunction
+
+autocmd! BufWritePre * :call <SID>StripTrailingWhitespaces()
+
 " Align cucumber tables
 inoremap <silent> <Bar>   <Bar><Esc>:call <SID>align()<CR>a