R: 3.6.3 --> 4.0.0 & update packages#86081

Merged

peti merged 3 commits intoNixOS:masterfrom

jabranham:update-r

May 1, 2020

Commits on Apr 26, 2020

Commits on Apr 29, 2020

Rstudio: 1.2.5033 -> 1.2.5042
jabranham
committed