update

git-svn-id: https://svn.r-project.org/R/trunk@63920 00db46b3-68df-0310-9c12-caf00c1e9a41
Link from ?require to ?requireNamespace.

git-svn-id: https://svn.r-project.org/R/trunk@63922 00db46b3-68df-0310-9c12-caf00c1e9a41
Correct comments.

git-svn-id: https://svn.r-project.org/R/trunk@63924 00db46b3-68df-0310-9c12-caf00c1e9a41
Note packages with VignetteBuilder: field but no 'build/vignette.rds'
in CRAN incoming checks.

git-svn-id: https://svn.r-project.org/R/trunk@63925 00db46b3-68df-0310-9c12-caf00c1e9a41
update

git-svn-id: https://svn.r-project.org/R/trunk@63926 00db46b3-68df-0310-9c12-caf00c1e9a41
clean up reports

git-svn-id: https://svn.r-project.org/R/trunk@63927 00db46b3-68df-0310-9c12-caf00c1e9a41