Base: Implement TimeElapsed

Some instances of TimeInfo serve the sole purpose of measuring time
duration. Using system time is unfortunate as it returns wall clock,
which is not guaranteed to be monotonic. Replace such a usage with
the new TimeElapsed class based on steady clock.

src/Mod/Part/Gui/TaskCheckGeometry.cpp

@@ -678,13 +678,13 @@ int TaskCheckGeometryResults::goBOPSingleCheck(const TopoDS_Shape& shapeIn, Resu
   BOPCheck.CurveOnSurfaceMode() = curveOnSurfaceMode;
 
 #ifdef FC_DEBUG
-  Base::TimeInfo start_time;
+  Base::TimeElapsed start_time;
 #endif
 
   BOPCheck.Perform();
 
 #ifdef FC_DEBUG
-  float bopAlgoTime = Base::TimeInfo::diffTimeF(start_time,Base::TimeInfo());
+  float bopAlgoTime = Base::TimeElapsed::diffTimeF(start_time, Base::TimeElapsed());
   std::cout << std::endl << "BopAlgo check time is: " << bopAlgoTime << std::endl << std::endl;
 #endif