0028417: Using PRECOMPILED HEADER to speed up compilation time

Use of Cotire tool is introduced for acceleration of CMake builds, by usage of precompiled headers.
CMake option BUILD_USE_PCH is added to enable / disable use of precompiled headers

When precompiled headers are used, additional compiler macros are defined globally in the build system to avoid problems due to different order of included files:
- NOMINMAX is defined on Windows to prevent defining "min" and "max" as macros by windows.h
- STRSAFE_NO_DEPRECATE and _SCL_SECURE_NO_WARNINGS are defined on Windows to prevent declaring functions of standard C library as deprecated by #pragma, and other warnings in system headers
- GL_GLEXT_LEGACY and GLX_GLEXT_LEGACY are defined to ensure that only OCCT's own glext.h is used
- __STDC_FORMAT_MACROS is defined to have standard C print format macros always defined

Code is corrected to avoid conflicts with system headers and in case of compiling together as unity builds (partially):
- Some locally defined variables in TKV3d, TKHLR are renamed to be unique
- Duplicated definitions of macros and global functions are eliminated in TKSTEP
- Useless header WNT_UInt.hxx is removed
- Usage of local variables conflicting with X11 macro is avoided in Draw_Viewer.cxx
- Local variables in AIS_ConcentricRelation.cxx are renamed to avoid conflict with macros defined in windows.h
- HXX files containing code are renamed to PXX or merged with corresponding CXX files.

IVtkTools classes are corrected to avoid compiler warnings disabled in non-PCH builds by inclusion of VTK headers.

Useless pragmas disabling warnings on MSVC are removed

src/SelectMgr/SelectMgr_SelectableObjectSet.cxx

@@ -197,7 +197,7 @@ namespace
     NCollection_IndexedMap<Handle(Select3D_HBndBox3d)> myBoundings;
   };
 
-  static const Graphic3d_Mat4d THE_IDENTITY_MAT;
+  static const Graphic3d_Mat4d SelectMgr_SelectableObjectSet_THE_IDENTITY_MAT;
 }
 
 //=============================================================================
@@ -360,7 +360,7 @@ void SelectMgr_SelectableObjectSet::UpdateBVH (const Handle(Graphic3d_Camera)& t
     {
       // construct adaptor over private fields to provide direct access for the BVH builder
       BVHBuilderAdaptorPersistent anAdaptor (myObjects[BVHSubset_2dPersistent],
-        theCamera, theProjectionMat, THE_IDENTITY_MAT, theViewportWidth, theViewportHeight);
+        theCamera, theProjectionMat, SelectMgr_SelectableObjectSet_THE_IDENTITY_MAT, theViewportWidth, theViewportHeight);
 
       // update corresponding BVH tree data structure
       myBuilder[BVHSubset_2dPersistent]->Build (&anAdaptor, myBVH[BVHSubset_2dPersistent].get(), anAdaptor.Box());

src/SelectMgr/SelectMgr_ViewerSelector.cxx

@@ -81,7 +81,7 @@ namespace {
     }
   }
 
-  static const Graphic3d_Mat4d THE_IDENTITY_MAT;
+  static const Graphic3d_Mat4d SelectMgr_ViewerSelector_THE_IDENTITY_MAT;
 }
 
 //==================================================
@@ -476,7 +476,7 @@ void SelectMgr_ViewerSelector::TraverseSensitives()
       // define corresponding frustum builder parameters
       Handle(SelectMgr_FrustumBuilder) aBuilder = new SelectMgr_FrustumBuilder();
       aBuilder->SetProjectionMatrix (mySelectingVolumeMgr.ProjectionMatrix());
-      aBuilder->SetWorldViewMatrix (THE_IDENTITY_MAT);
+      aBuilder->SetWorldViewMatrix (SelectMgr_ViewerSelector_THE_IDENTITY_MAT);
       aBuilder->SetWindowSize (aWidth, aHeight);
       aMgr = mySelectingVolumeMgr.ScaleAndTransform (1, aTFrustum, aBuilder);
     }
@@ -489,7 +489,7 @@ void SelectMgr_ViewerSelector::TraverseSensitives()
     const Graphic3d_Mat4d& aProjectionMat   = mySelectingVolumeMgr.ProjectionMatrix();
     const Graphic3d_Mat4d& aWorldViewMat    = aBVHSubset != SelectMgr_SelectableObjectSet::BVHSubset_2dPersistent
                                             ? mySelectingVolumeMgr.WorldViewMatrix()
-                                            : THE_IDENTITY_MAT;
+                                            : SelectMgr_ViewerSelector_THE_IDENTITY_MAT;
 
     const opencascade::handle<BVH_Tree<Standard_Real, 3> >& aBVHTree = mySelectableObjects.BVH (aBVHSubset);