Add usage example comment

Change-Id: Id7f122a2d129d70192e8bc493b0bd2423558187b

bin/benchmark-document-loading

@@ -26,6 +26,12 @@
 # in which case the provisions of the GPLv3+ or the LGPLv3+ are applicable
 # instead of those above.
 
+# Simple script to load a bunch of documents and export them as Flat ODF
+#
+# Personally I run it using a loop like this:
+# while :; do ~/lo/master-suse/instdir/unxlngx6/program/python ~/lo/master-suse/bin/benchmark-document-loading  --soffice=path:/home/tml/lo/master-suse/instdir/unxlngx6/program/soffice --outdir=file://$PWD/out --userdir=file:///tmp/test $PWD/docs; sleep 10; done
+#
+
 import datetime
 import getopt
 import os