0023934: Compiler warnings in MS VC++ 10

Elimination of compiler warnings
- ExprIntrp: generated file ExprIntrp.tab.c and related WOK scripts removed from the sources
- ExprIntrp, StepFile: added missing declarations and casts; warnings caused by Flex and Bison code suppressed for MSVC compuler by #pragma
- OSD: dummy #includes added to files containing no code for Windows, to avoid warning on empty file
- PLib: piece of code contained in PLib_ChangeDim.gxx included explicitly in cxx and cleaned
- Other places: some casts added to avoid warnings

src/Geom2dAPI/Geom2dAPI_InterCurveCurve.cxx

@@ -225,8 +225,7 @@ void Geom2dAPI_InterCurveCurve::Segment (const Standard_Integer Index,
                                          Handle(Geom2d_Curve)&) const 
 {
   Standard_NotImplemented::Raise(" ");
-
+  (void)Index; // avoid compiler warning in Release mode
   Standard_OutOfRange_Raise_if(Index < 0 || Index > NbSegments(),
 			       "Geom2dAPI_InterCurveCurve::Segment");
-
 }