Add missing classes

app/include/fan/Aggregators.h

@@ -0,0 +1,27 @@
+#ifndef AGGREGATORS_H_
+#define AGGREGATORS_H_
+
+#include <sensor/Sensor.h>
+
+class Aggregator
+{
+public:
+  virtual int aggregate(std::vector<std::shared_ptr<Sensor>> sensors) const = 0;
+  virtual const std::string toString() const = 0;
+};
+
+class AverageAggregator : public Aggregator
+{
+public:
+  int aggregate(std::vector<std::shared_ptr<Sensor>> sensors) const override;
+  const std::string toString() const override;
+};
+
+class MaxAggregator : public Aggregator
+{
+public:
+  int aggregate(std::vector<std::shared_ptr<Sensor>> sensors) const override;
+  const std::string toString() const override;
+};
+
+#endif // AGGERGATORS_H_