resolve is publisher is on crossref

[maxheld83]

this is a good list that could be gotten off of CR.
Might belong into CR pkg.
Overlaps with subugoe/biblids#23

[maxheld83]

had this:

is_doi_on_cr <- function(x) {
  res <- httr::HEAD(
    url = paste0("https://api.crossref.org/works/", x)
  )
  if (res$status_code == 200) {
    return(TRUE)
  } else if (res$status_code == 404) {
    return(FALSE)
  } else {
    httr::stop_for_status(res)
  }
}