Keep bracketed paste enabled in normal and visual mode

The mappings are already in place, but are unused without this change.
In command line mode the escape sequences are mapped to <nop>, so they
will be ignored and keeping bracketed paste enabled all the time should
cause no trouble.

Author: ssiegel

plugin/bracketed-paste.vim

@@ -24,8 +24,8 @@ function! WrapForTmux(s)
   return tmux_start . substitute(a:s, "\<Esc>", "\<Esc>\<Esc>", 'g') . tmux_end
 endfunction
 
-let &t_SI .= WrapForTmux("\<Esc>[?2004h")
-let &t_EI .= WrapForTmux("\<Esc>[?2004l")
+let &t_ti .= WrapForTmux("\<Esc>[?2004h")
+let &t_te .= WrapForTmux("\<Esc>[?2004l")
 
 function! XTermPasteBegin(ret)
   set pastetoggle=<f29>