Add documentation for URL, OUT arrays

update.cfg.example

@@ -17,6 +17,16 @@
 #BACKUPSUFFIX=
 #BLOCKLIST=$WORKDIR/block.list
 #LIST_DIR=$WORKDIR/lists
+
+# Simple URL grab list
+# Mirror any URL to the 'lists' directory.
+# Note: URL and OUT indices are correlated, e.g. URL[10] will be retrieved and
+# stored in OUT[10]
+# Example config:
+#   URL+=('https://example.com/mylist.hosts')
+#   OUT+=("$LIST_DIR/mylist.hosts")
+#   URL+=('https://example.com/others.hosts')
+#   OUT+=("$LIST_DIR/others.hosts")
 #OUT=()
 #URL=()