Fixed sediment yield parser. * Fixed loading files ending with '_Sand.csv'. There are different files ending like this, containing different data sets. * Added new file ending. Naming for files is different in single year and official epochs.

SYMBOLSET
SYMBOL
  NAME 'point'
  TYPE ELLIPSE
  POINTS
    1 1
  END
  FILLED TRUE
END
SYMBOL
  NAME "square"
  TYPE VECTOR
  POINTS
    0 0
    0 1
    1 1
    1 0
    0 0
  END
  FILLED TRUE
END
END