bug#38044: 27.0.50; There should be an easier way to look at a specific vc commit

[Eli Zaretskii]

> Cc: larsi@gnus.org, stephen.berman@gmx.net, 38044@debbugs.gnu.org,
>  juri@linkov.net
> From: Dmitry Gutov <dgutov@yandex.ru>
> Date: Fri, 22 Nov 2019 23:43:08 +0200
> 
> For Git, we need 'git log -p -n 1', for Hg, 'hg log -p -l 1'.

Btw, it looks like only Git and Src need to explicitly limit the
output of 'log' to just a single revision, others have a way of
specifying a single revision for 'log'.  They all use "-r REVISION"
for that.