Import utils for URL-coding

Change-Id: Ide21a11542e8e77abfe88f1de13cb101d09b2ea6
diff --git a/R/KorAPConnection.R b/R/KorAPConnection.R
index 5ecd11c..4959e45 100644
--- a/R/KorAPConnection.R
+++ b/R/KorAPConnection.R
@@ -1,5 +1,6 @@
 #' @import jsonlite
 #' @import curl
+#' @import utils
 
 defaultKorAPUrl <- "https://korap.ids-mannheim.de/"