visual feedback on vim-ipython shell update

Author: ivanov

ftplugin/python/ipy.vim

@@ -351,7 +351,7 @@ map <silent> <F5> :python run_this_file()<CR>
 map <silent> <S-F5> :python run_this_line()<CR>
 map <silent> <F9> :python run_these_lines()<CR>
 map <silent> <leader>d :py get_doc_buffer()<CR>
-map <silent> <leader>s :py update_subchannel_msgs()<CR>
+map <silent> <leader>s :py update_subchannel_msgs(); echo("vim-ipython shell updated",'Operator')<CR>
 map <silent> <S-F9> :python toggle_reselect()<CR>
 "map <silent> <C-F6> :python send('%pdb')<CR>
 "map <silent> <F6> :python set_breakpoint()<CR>