Fixing the heat equation.

examples/heat-equation/CMakeLists.txt

examples/heat-equation/Makefile

examples/heat-equation/heatEquationSetter.h

examples/heat-equation/heatEquationSetter_impl.h

examples/heat-equation/tnl-heat-equation.cpp

src/CMakeLists.txt

src/functions/CMakeLists.txt

src/functions/tnlConstantFunction.h

src/functions/tnlExpBumpFunction.h

src/functions/tnlSinBumpsFunction.h

src/functions/tnlSinWaveFunction.h

src/implementation/functions/CMakeLists.txt

src/implementation/operators/CMakeLists.txt

src/implementation/operators/diffusion/CMakeLists.txt

src/operators/CMakeLists.txt

src/operators/diffusion/CMakeLists.txt