code manually merged with devel.
Ready for debugging.
UPDATE: mpi_ version of the code updated and slightly tested with positive
results.

+ parallel environment updated to an ED specific one (ED_MPI_xx variables), this
avoid overlap of different parallel environments (e.g. in RDMFT).
+ test performed on multi-band antiferro problem (BHZ-AFM) so to check all toghether
the different aspects.
+ arpack routines collects in two files
+ bath parameters save as .used before the calculations and as .restart after the fit.

Ready to merge with devel branch. Waiting for more tests.