data/logic/ui: added aggregation edges

This change adds the creation of aggregation edges to the StorageGraph, which save the connection counts between
children in their parents. Aggregation edges are displayed using a straight line, that is thicker than more connections
it represents with the connection count in the middle.

src/lib/data/graph/token_component/TokenComponentAggregation.cpp

@@ -0,0 +1,29 @@
+#include "data/graph/token_component/TokenComponentAggregation.h"
+
+TokenComponentAggregation::TokenComponentAggregation()
+{
+}
+
+TokenComponentAggregation::~TokenComponentAggregation()
+{
+}
+
+std::shared_ptr<TokenComponent> TokenComponentAggregation::copy() const
+{
+	return std::make_shared<TokenComponentAggregation>(*this);
+}
+
+int TokenComponentAggregation::getAggregationCount() const
+{
+	return m_ids.size();
+}
+
+void TokenComponentAggregation::addAggregationId(Id id)
+{
+	m_ids.insert(id);
+}
+
+const std::set<Id>& TokenComponentAggregation::getAggregationIds() const
+{
+	return m_ids;
+}

src/lib/data/graph/token_component/TokenComponentAggregation.h

@@ -0,0 +1,27 @@
+#ifndef TOKEN_COMPONENT_AGGREGATION_H
+#define TOKEN_COMPONENT_AGGREGATION_H
+
+#include <set>
+
+#include "utility/types.h"
+
+#include "data/graph/token_component/TokenComponent.h"
+
+class TokenComponentAggregation
+	: public TokenComponent
+{
+public:
+	TokenComponentAggregation();
+	virtual ~TokenComponentAggregation();
+
+	virtual std::shared_ptr<TokenComponent> copy() const;
+
+	int getAggregationCount() const;
+	void addAggregationId(Id id);
+	const std::set<Id>& getAggregationIds() const;
+
+private:
+	std::set<Id> m_ids;
+};
+
+#endif // TOKEN_COMPONENT_AGGREGATION_H