[det]el_bind(+In:stream,
+Args)bind command with the given arguments.
The example below lists the current key bindings.
?- el_bind(user_input, ['-a']).
The predicate el_bind/2 is
typically used to bind commands defined using el_addfn/4.
Note that the C proxy function has only the last character of the
command as context to find the Prolog binding. This implies we cannot
both bind e.g., "^[?" *and "?" to a Prolog function.