Refactorization of Timer and TimeDependentPDESolver.

src/TNL/Experimental/Hamilton-Jacobi/Solvers/CMakeLists.txt

...olvers/hamilton-jacobi/tnlDirectEikonalMethodsBase_impl.h

...bi/Solvers/hamilton-jacobi/tnlDirectEikonalProblem_impl.h

...on-Jacobi/Solvers/hamilton-jacobi/tnlFastSweepingMethod.h

...bi/Solvers/hamilton-jacobi/tnlFastSweepingMethod1D_impl.h

...bi/Solvers/hamilton-jacobi/tnlFastSweepingMethod2D_impl.h

...bi/Solvers/hamilton-jacobi/tnlFastSweepingMethod3D_impl.h

src/TNL/Math.h

src/TNL/Solvers/PDE/CMakeLists.txt

src/TNL/Solvers/PDE/ExplicitTimeStepper.h

src/TNL/Solvers/PDE/ExplicitTimeStepper_impl.h

src/TNL/Solvers/PDE/PDESolver.h

src/TNL/Solvers/PDE/PDESolver_impl.h

src/TNL/Solvers/PDE/SemiImplicitTimeStepper.h

src/TNL/Solvers/PDE/SemiImplicitTimeStepper_impl.h

src/TNL/Solvers/PDE/TimeDependentPDESolver.h

src/TNL/Solvers/PDE/TimeDependentPDESolver_impl.h

src/TNL/Solvers/PDE/TimeIndependentPDESolver.h

src/TNL/Solvers/PDE/TimeIndependentPDESolver_impl.h

src/TNL/Solvers/SolverStarter_impl.h