[R-SIG-Mac] Availability of nightly R-devel build

[Jim Hester]

It seems the nightly R-devel builds have stopped updating. The last
one available seems to be from April 5th, R Under development
(unstable) (2018-04-05 r74542)

That also seems to be the date of the last log available at
http://r.research.att.com/log-R-devel.el-capitan.x86_64.html

I did not see anything on the maining list about this being
deliberate, apologies if I missed something.

Jim