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/LocatedAccessPoint.h

@@ -6,7 +6,7 @@
 #include "../../floorplan/v2/Floorplan.h"
 
 /**
- * describes an access-point including its position
+ * describes an access-point including its position (in meter)
  */
 class LocatedAccessPoint : public AccessPoint, public Point3 {