0026980: Intersection algorithm spends much system time and system memory

0026980: Intersection algorithm spends much system time and system memory

1. Step of Walking-line has been increased as possible and now computes by iteratively adaptive algorithm (every iteration checks if current step is too big/small and decreases/increases one).

2. Interface of IntWalk_PWalking class has been changed
2.1. Method MaxStep() has been added in order to know about maximal distance between 2D-points.
2.2. Method ComputePasInit(...) has been added in order to initial step value computation.
2.3. Fields myTolTang (tolerance for intersection algorithm) and myStepMin (minimal step value) have been added.

Correction of some test cases.
Creation test case for this issue.
Changes to eliminate compiler warnings.