code: public static Map<String, String[]> readMap(String filename)
  			throws IOException {
  		return readMap(filename, DEFAULT_DELIMITER);
  	}
docs: Reads the specified file into a map. The first value is used as key. The
  rest is put into a list and used as map value. Each entry is one line of
  the file.
  <p>
  Ensures that no null value is returned.
  <p>
  Uses the default {@link #DEFAULT_DELIMITER}
  
  @param filename
  the name of the specification file (not the path to it)
  @return a map with the first column as keys and the other columns as
  values.
  @throws IOException
  if unable to read the specification file