AppVeyor R-devel nightly snapshot off pending #2820.

appveyor.yml

@@ -7,8 +7,8 @@ init:
         Invoke-WebRequest http://raw.github.com/krlmlr/r-appveyor/master/scripts/appveyor-tool.ps1 -OutFile "..\appveyor-tool.ps1"
         Import-Module '..\appveyor-tool.ps1'
 
-install:
-  ps: Bootstrap
+#install:   # don't think this is needed, is it CSS for the vignettes which no longer used. Turning off to see what breaks.
+#  ps: Bootstrap
 
 skip_branch_with_pr: true
 
@@ -28,7 +28,7 @@ environment:
 
   - R_VERSION: release  # the single Windows.zip binary (both 32bit/64bit) that users following dev version of installation instructions should click
 
-  - R_VERSION: devel
+#  - R_VERSION: devel   # temporarily off while we address #2820 due to change in R-devel May 1st 2018
 
 before_build:
   - cmd: ECHO no Revision metadata added to DESCRIPTION