[bug#32176] Add emacs-adoc-mode

[Jack Hill]

On Tue, 17 Jul 2018, Leo Famulari wrote:

> I added a copyright line for you to the emacs module.

Awesome, thank you.

> I also made sure the descriptions were composed of complete sentences,
> as requested in the manual section Synopses and Descriptions:
>
> https://www.gnu.org/software/guix/manual/en/html_node/Synopses-and-Descriptions.html

Oops, sorry. Thanks for the fix. I'll be more careful of that in the 
future.

Best,
Jack