Update references in DESCRIPTION and readme files

[jeroen]

We should update references from ropensci.github.io/{pkg} to docs.ropensci.org/{pkg} in the readme and description files.

• Review: https://github.com/search?q=org%3Aropensci+%22ropensci.github.io%22+filename%3ADESCRIPTION&type=Code
• Review: https://github.com/search?q=org%3Aropensci+%22ropensci.github.io%22+filename%3Areadme&type=Code
• Review all DESCRIPTION files without docs.ropensci.org reference

packages <- jsonlite::fromJSON("https://ropensci.github.io/roregistry/registry.json")$packages
packages <- subset(packages, grepl('https://github.com/ropensci/', url))
packages$hasdocs <- sapply(packages$name, function(pkg){
  url <- sprintf('https://docs.ropensci.org/%s/pkgdown.yml', pkg)
  message("checking: ", url)
  req <- curl::curl_fetch_memory(url)
  return(req$status == 200)
})
packages$hasurl <- sapply(packages$name, function(pkg){
  url <- sprintf('https://github.com/ropensci/%s/raw/master/DESCRIPTION', pkg)
  message("checking: ", url)
  req <- curl::curl_fetch_memory(url)
  grepl("docs.ropensci.org", rawToChar(req$content), fixed = TRUE)
})
subset(packages, hasdocs == T & hasurl == F)$name