Drop explicit host ports Compose will automatically allocate unassigned ports. These can be looked up e.g. using `docker compose port'. Enables using several "instances" of the application with different project names (`docker compose -p <project name>').

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