gfio: add per-job option view

The option view is now a master notebook of jobs that got added
from a given job file, with each tab holding a new notebook
with tabs for the options.

This is pretty slow for big jobs. Adding eg the 1mbs-clients.fio
example job file shows this nicely, since it contains 32 jobs.
Will need to look into how to speed this up.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/gfio.h b/gfio.h
index 854f7ad..dd69c54 100644
--- a/gfio.h
+++ b/gfio.h
@@ -145,7 +145,9 @@
 	struct gui_entry *ge;
 	struct fio_client *client;
 	GtkWidget *err_entry;
+
 	struct flist_head o_list;
+	unsigned int o_list_nr;
 
 	struct end_results *results;
 	unsigned int nr_results;