COMPMID-2452: Add mnist example

* Add small-mnist example
* Add PrintAccessor
* Add DequantizationLayer graph node

Change-Id: I7bc8011e5a602f40fa3c47b231a2a69c804e78c2
Signed-off-by: Isabella Gottardi <isabella.gottardi@arm.com>
Reviewed-on: https://review.mlplatform.org/c/2274
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Giorgio Arena <giorgio.arena@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
diff --git a/arm_compute/graph/nodes/Nodes.h b/arm_compute/graph/nodes/Nodes.h
index 1586270..7b586b8 100644
--- a/arm_compute/graph/nodes/Nodes.h
+++ b/arm_compute/graph/nodes/Nodes.h
@@ -33,6 +33,7 @@
 #include "arm_compute/graph/nodes/ConvolutionLayerNode.h"
 #include "arm_compute/graph/nodes/DeconvolutionLayerNode.h"
 #include "arm_compute/graph/nodes/DepthwiseConvolutionLayerNode.h"
+#include "arm_compute/graph/nodes/DequantizationLayerNode.h"
 #include "arm_compute/graph/nodes/DetectionOutputLayerNode.h"
 #include "arm_compute/graph/nodes/DetectionPostProcessLayerNode.h"
 #include "arm_compute/graph/nodes/DummyNode.h"