Corrected some links due to CRAN mail:
Found the following (possibly) invalid URLs:
URL: https://cran.r-project.org/web/packages/CSTools/index.html
From: README.md
Status: 200
Message: OK
CRAN URL not in canonical form
URL: https://cran.r-project.org/web/packages/s2dv/index.html
From: README.md
Status: 200
Message: OK
CRAN URL not in canonical form
URL: https://cran.r-project.org/web/packages/startR/index.html
From: README.md
Status: 200
Message: OK
CRAN URL not in canonical form
The canonical URL of the CRAN page for a package is
https://CRAN.R-project.org/package=pkgname
Please fix and resubmit.