Adding the first CUDA version.
	modified:   INSTALL
	new file:   cuda.py
	new file:   src/cu_elastic.cu
	new file:   src/cu_fft.cu
	new file:   src/cu_include.h
	new file:   src/curelax.f90
	modified:   src/elastic3d.f90
	modified:   src/export.f90
	modified:   src/friction3d.f90
	modified:   src/green.f90
	new file:   src/papi_prof.c
	modified:   src/viscoelastic3d.f90
	modified:   wscript