DiscreteFrechetDistance fails to use initial points of lines

[mdavis]

As reported in ​PG-4992, the distance calculated by DiscreteFrechetDistance for the following lines appears to be incorrect:

A: LINESTRING (1 1, 2 2)
B: LINESTRING (1 4, 2 3)

The computed result is 2.23606797749979. But the Frechet Distance must be at least the distance between the initial points of the lines, which is 3.

Resolution

It appears that there is a bug in ​this line. It should be

   ca[i][j] = p_ptDist;

This gives the correct answer for the above case. All other tests pass.

[mdavis]

Fixed by ​848f978b89