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/WiFiProbability.h

@@ -0,0 +1,15 @@
+#ifndef WIFPROBABILITY_H
+#define WIFPROBABILITY_H
+
+#include "WiFiMeasurements.h"
+
+/**
+ * base class for all WiFi probability calculators.
+ * such a calculator determines the probabilty for a location (e.g. x,y,z)
+ * given WiFiMeasurements
+ */
+class WiFiProbability {
+
+};
+
+#endif // WIFPROBABILITY_H