bug#18100: 24.4.50; Restore simplicity of (put 'self-insert-command 'delete-selection 'kill)

[Juri Linkov]

>   Users should be able to `put' a single,
>   understandable symbol as the `delete-selection'
>   property value.  They should not need to fiddle
>   with obscure lambda forms (or symbols whose names
>   are not simple to understand).  Symbol `kill' is
>   simple - it says that you want the region to be killed.

What symbol name do you propose?