added compiler switches for gfortran and ifort to check for standard conformity
old gnu compilers <4.4 are not longer supported because they don't provide the c binding for fftw
* Marc: node displacements are added to initial node coordinates (mesh_node0) to get current node positions (mesh_node), then ip coordinates are deduced
* Abaqus: ip coordinates are directly updated, no update of node coordinates!
* Spectral: for the moment no update of either ip or node coordinates! passing only dummy values with initial ip coordinates