0029866: Intersector returns two overlapped curves as a result

0029866: Intersector returns two overlapped curves as a result

Since now a new WLine is not created if its start point lies in another earlier computed WLine. It allows avoiding creation of duplicate WLines in the intersection result.

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1. Methods IsOutSurf1Box(...), IsOutSurf2Box(...), IsOutBox(...) for classes IntSurf_LineOn2S and IntPatch_RLine have been created.