bug#26786: [PATCH] gnu: emacs-org: Update to 20170502.

[Arun Isaac]

>>>> I think we should build directly from org's release tarball at
>>>> http://orgmode.org/org-9.0.6.tar.gz instead of using the ELPA
>>>> tarball. It somehow feels like we are not building from source but
>>>> rather relying on a prepackaged tarball from ELPA. However, Nicolas
>>>> Goaziou, the org mode maintainer,
>>>> disagrees. 
>>>> https://lists.gnu.org/archive/html/guix-devel/2016-08/msg01395.html
>>>
>>> I find Nicolas’s argument above (that building from ELPA makes the
>>> recipe trivial) pretty convincing.
>>>
>>> Why would you suggest using the tarball from orgmode.org?
>>
>> It seems like we are depending on an intermediary (ELPA) instead of
>> directly building from the original source. I feel that Guix packages
>> should not depend on other repositories (like ELPA).
>
> I agree with this sentiment, but my understanding is that ELPA is not
> really an “intermediary”: package maintainers upload directly there, and
> some upload only there.  So I think it’s OK.  Thoughts?

Yeah, it's not a big deal. We could think of ELPA as some kind of "dual
hosting", instead of as an "intermediary".