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

grid/GridPoint.h

@@ -35,6 +35,12 @@ struct GridPoint {
 		return x_cm != o.x_cm || y_cm != o.y_cm || z_cm != o.z_cm;
 	}
 
+	GridPoint operator * (const float f) const {return GridPoint(x_cm*f, y_cm*f, z_cm*f);}
+
+	GridPoint& operator += (const GridPoint& o) {x_cm += o.x_cm; y_cm += o.y_cm; z_cm += o.z_cm; return *this;}
+
+	GridPoint& operator /= (const float f) {x_cm /= f; y_cm /= f; z_cm /= f; return *this;}
+
 	/** get the distance (in meter) betwen this and the given point */
 	float getDistanceInMeter(const GridPoint& other) const {
 		return getDistanceInCM(other) / 100.0f;