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

geo/Point2.h

@@ -47,6 +47,10 @@ struct Point2 {
 
 	Point2 normalized() const {return (*this) / length();}
 
+	Point2 rotated(const float rad) const {
+		return Point2(x*std::cos(rad)-y*std::sin(rad), x*std::sin(rad)+y*std::cos(rad));
+	}
+
 	/** get the distance between this point and the other one */
 	float getDistance(const Point2& o) const {
 		const float dx = x - o.x;