add palette-datatypes.png

Signed-off-by: aradermache <ansgar.radermacher@cea.fr>

systemdes/system-design.adoc

@@ -44,7 +44,7 @@ We may now define the system whose default name is System:
 
 Here is the resulting diagram:
 
-image:system-from.scratch.png[System from scratch] +
+image:figs/figs/system-from.scratch.png[System from scratch] +
 System from scratch
 
 Here is the illustrated procedure: