updated urlencode.sh

bin/urlencode.sh

@@ -29,4 +29,7 @@ if type -P perl &>/dev/null &&
 elif type -p python3 &>/dev/null &&
      python3 -c 'from urllib.parse import quote_plus'; then
      python3 -c 'from urllib.parse import quote_plus; import sys; print(quote_plus(sys.stdin.read().rstrip("\n").rstrip("\r")))'
+else
+    echo "Neither Perl URI::Escape nor Python3 with UrlLib.Parse are available" >&2
+    exit 1
 fi