g1_level1 handle surface level type

grib 1 file has low cloud cover grib message. 
indicatorOfParameter = 186;
 indicatorOfParameter = 186;
  # Surface  (of the Earth, which includes sea surface)  (grib1/3.table)  
  indicatorOfTypeOfLevel = 1;
  level = 0;

This pull request is to update the rules to handle this type of level.