Getting closer to the goal of persistent spatial interpolation objects. There are no "initialize" and "getQualityRating" anymore, the initializations are performed by "getQualityRating". The arguments that used to be passed to the constructors are now split between constructor and getQualityRating. A few hacks will have to be removed: we should be able to get rid of some of the callbacks, the plain copy of Date and Dem will have to be avoided (most probably by working with pointers) and the map of objects that has been implemented (but commented out) will be enabled. So, a few hacks remain, but this is already a nice, big step forward!