huge commit

- worked on about everything
- grid walker using plugable modules
- wifi models
- new distributions
- worked on geometric data-structures
- added typesafe timestamps
- worked on grid-building
- added sensor-classes
- added sensor analysis (step-detection, turn-detection)
- offline data reader
- many test-cases

sensors/radio/WiFiMeasurement.h

@@ -0,0 +1,50 @@
+#ifndef WIFIMEASUREMENT_H
+#define WIFIMEASUREMENT_H
+
+#include "AccessPoint.h"
+#include "../../data/Timestamp.h"
+
+/**
+ * describes a measurement received for one access-point at a given time
+ */
+class WiFiMeasurement {
+
+private:
+
+	friend class VAPGrouper;
+
+	/** the access-point we got a measurement for */
+	AccessPoint ap;
+
+	/** the measured signal strength */
+	float rssi;
+
+	/** OPTIONAL. timestamp the measurement was recorded at */
+	Timestamp ts;
+
+public:
+
+	/** ctor */
+	WiFiMeasurement(const AccessPoint& ap, const float rssi) : ap(ap), rssi(rssi) {
+		;
+	}
+
+	/** ctor with timestamp */
+	WiFiMeasurement(const AccessPoint& ap, const float rssi, const Timestamp ts) : ap(ap), rssi(rssi), ts(ts) {
+		;
+	}
+
+public:
+
+	/** get the AP we got the measurement for */
+	const AccessPoint& getAP() const {return ap;}
+
+	/** get the measurement's signal strength */
+	float getRSSI() const {return rssi;}
+
+	/** OPTIONAL: get the measurement's timestamp (if known!) */
+	const Timestamp& getTimestamp() const {return ts;}
+
+};
+
+#endif // WIFIMEASUREMENT_H