added beacon stuff similiar architecture then wifi \n added activity percentage stuff \n added testcases

sensors/beacon/BeaconMeasurements.h

@@ -0,0 +1,26 @@
+#ifndef BEACONMEASUREMENTS_H
+#define BEACONMEASUREMENTS_H
+
+#include <vector>
+
+#include "BeaconMeasurement.h"
+
+/**
+ * group of several beacon measurements
+ */
+struct BeaconMeasurements {
+
+    std::vector<BeaconMeasurement> entries;
+
+    /** remove entries older then 3000 ms*/
+    void removeOld(const Timestamp latestTS) {
+        auto lambda = [latestTS] (const BeaconMeasurement& e) {
+            Timestamp age = latestTS - e.getTimestamp();
+            return age > Timestamp::fromMS(1000*3);
+        };
+        entries.erase(std::remove_if(entries.begin(), entries.end(), lambda), entries.end());
+    }
+
+};
+
+#endif // BEACONMEASUREMENTS_H