Write TT_MatchLength() and TT_MapLength()

[edwardsmarc]

TT_MatchLength will calculate the length of a field and check the returned integer is in a string list of integers.

TT_MapLengthInt will calculate the length of a field and map the returned integer to another integer.

For use in qc03 NUM_OF_LAYERS.

[edwardsmarc]

These functions are no longer needed. Consider removing.