ROTATE_LT n gl rotates a goal list gl by n places.
For n >= 0, this means moving the first n goals to the end of the list.
A negative n means rotating the list in the opposite direction.
FAILURE
Never fails.
EXAMPLE
To bring the third goal to first position, leaving the others in order, use
SPLIT_LT 3 (ROTATE_LT ~1, ALL_LT)
COMMENTS
Using SPLIT_LT, ROTATE_LT and REVERSE_LT,
any reordering of a list of goals is possible.