Scripts tnl-compile and tnl-link were added.

Min. interations feature was fixed in the GMRES method.
Timers for explicit and semi-implicit timestepping were added.

Parallel reduction in CUDA fixed.
Boundary conditions in linear system assembler fixed.
Min. iterations for linear solvers fixed.

Adding --fast-build optin for the build script to speed-up compilation.

Debugging GMRES solver.

It does not work and it needs to be fixed soon.

matrix assembler.