ui: Show call graphs, inheritance trees and include trees for active symbol (issue 249 337)

* Added TrailLayouter with Sugiyama dependency layouting
* Layouter supports horizontal and vertical layouts
* Added basic ui to graph view for showing incoming and outgoing paths
* Added depth slider, with infinity at maximum
* Disable trail ui when not available
* Added trail messages to undo stack and only use last one when undoing
* Added QtGraphLineBezier for trail graphs and refactored other line types
* Disabled edge activation for trail layouts, shown only visually
* Highlight all connected edges when hovering a node in trail layout
* Use different color when highlighting call edges for better contrast
* Fixed BucketLayouter issue when edge does not leave node
* Increased click area for angled edges

bug id = 249 337

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src/lib/utility/messaging/type/MessageActivateTrail.h

@@ -0,0 +1,32 @@
+#ifndef MESSAGE_ACTIVATE_TRAIL_H
+#define MESSAGE_ACTIVATE_TRAIL_H
+
+#include "utility/messaging/Message.h"
+#include "utility/types.h"
+
+class MessageActivateTrail
+	: public Message<MessageActivateTrail>
+{
+public:
+	MessageActivateTrail(Id originId, Id targetId, Edge::EdgeTypeMask trailType, size_t depth, bool horizontalLayout)
+		: originId(originId)
+		, targetId(targetId)
+		, trailType(trailType)
+		, depth(depth)
+		, horizontalLayout(horizontalLayout)
+	{
+	}
+
+	static const std::string getStaticType()
+	{
+		return "MessageActivateTrail";
+	}
+
+	const Id originId;
+	const Id targetId;
+	const Edge::EdgeTypeMask trailType;
+	const size_t depth;
+	const bool horizontalLayout;
+};
+
+#endif // MESSAGE_ACTIVATE_TRAIL_H