adding self.ext to DataPump classes, plus some path management
improving FileName class functionality by converting getter methods to properties
replacing parse_time with faster variant after bug was fixed in pandas.dataframe.to_datetime
API change for fu.FileName members. (-> properties, and identifier changed)
typo
removing obsolete functions
replacing by prepare_data to follow DRY principle
adding L1ADataFile class and open_and_accumulate function
Added production of temperatures and radiances for calib data as well.
closes #42