bug#52245: Wishlist: cycle input methods

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Cc: Robert Pluim <rpluim@gmail.com>,  andremegafone@gmail.com,
>   tor.a.s.kringeland@ntnu.no,  52245@debbugs.gnu.org
> Date: Thu, 23 Dec 2021 20:02:33 +0200
> 
>   C-1 C-\  activates the first input methods in the list of input methods
>   C-2 C-\  second
>   C-3 C-\  third
>   ...
>   C-0 C-\  deactivates the currently active input method

The problem with this system is that the user needs to remember which
IM is the first and which the second.