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/Draw/Draw_Viewer.cxx

@@ -926,14 +926,13 @@ Draw_Display Draw_Viewer::MakeDisplay (const Standard_Integer id) const
   if (Draw_Batch) {Draw_Display dis;return dis;}
   curviewId = id;
   curview = myViews[id];
-  int GXcopy = 0x3;
   nbseg = 0;
   Draw_Color initcol(Draw_blanc);
   // to force setting the color
   currentcolor = Draw_Color(Draw_rouge);
   Draw_Display dis;
   dis.SetColor(initcol);
-  dis.SetMode(GXcopy);
+  dis.SetMode(0x3 /*GXcopy*/);
   return dis;
 }