[gegl] red-eye-removal: add reference hash

[Øyvind Kolås <ok src gnome org>]

commit c96a801d3085fa07db314a2c80f682fc798c2fd0
Author: Øyvind Kolås <pippin gimp org>
Date:   Sat Oct 14 03:28:30 2017 +0200

    red-eye-removal: add reference hash
    
    in the example image there is no red eye, but the parts of the rock cliff in
    the background with reddish hues are taken towards black; a selection of the
    red eye is meant to be done before applying the filter - thus this is a valid
    cached hash for a good result.

 operations/common-gpl3+/red-eye-removal.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/operations/common-gpl3+/red-eye-removal.c b/operations/common-gpl3+/red-eye-removal.c
index 5b8aa76..25bec4c 100644
--- a/operations/common-gpl3+/red-eye-removal.c
+++ b/operations/common-gpl3+/red-eye-removal.c
@@ -170,6 +170,7 @@ gegl_op_class_init (GeglOpClass *klass)
     "title",       _("Red Eye Removal"),
     "categories",  "enhance",
     "license",     "GPL3+",
+    "reference-hash", "9555ca69e41070d7a316bf87004adf5c",
     "description", _("Remove the red eye effect caused by camera flashes"),
     NULL);
 }