Start using creationDate rather than pubDate

Change-Id: I131d8396ff592dbfeea890e515cb6aceb9038c98
diff --git a/R/misc.R b/R/misc.R
index 108d942..0692619 100644
--- a/R/misc.R
+++ b/R/misc.R
@@ -78,9 +78,9 @@
 #' @export
 queryStringToLabel <- function(data, pubDateOnly = FALSE, excludePubDate = FALSE) {
   if (pubDateOnly) {
-    data <-substring(data, regexpr("pubDate", data)+7)
+    data <-substring(data, regexpr("(pub|creation)Date", data)+7)
   } else if(excludePubDate) {
-    data <-substring(data, 1, regexpr("pubDate", data))
+    data <-substring(data, 1, regexpr("(pub|creation)Date", data))
   }
   leftCommon = lcpCount(data)
   while (leftCommon > 0 && grepl("[[:alnum:]/=.*!]", substring(data[1], leftCommon, leftCommon))) {