GSNIO: reading of meteo data works now. However there are the usual GSN issues, which are plentiful and painful:
1) Big problem: NULL values seem to actually come as 0 values
2) parameter naming conventions: totally inconsistent, also one station might have more than one sensor for a parameter, which one to use?
3) Slow, impossible to retrieve meta data for one station only, meta data formatted in obscure way -> necessary to guess where the timestamp is (current guess position 1 or 2 in the csv formatted data row).