Removed the commented codes of KA52clay() and KA52sand from the monica-parameters.cpp since they are implemented in the conversion.cpp; relative humidity is now not required by monica; if values < 0 are read in from the input files, the dataaccessor for relhumid is left empty; before passing the relhumid-values into the cropstep and generalstep methods, there was added a check, if data for relhumid are available; if not, -1 is passed into the methods