some updates:
-spline --> interpolate: a more compact module for interpolation.
-tools_bethe --> functions_bethe: Bethe Lattice related functions moved into FUNCTIONS with
some density of states and gaussian.
-some improvements in STATISTICS for histogram routines
BUG fixed in FFTGF: fft from iw to tau (fftgf_iw2tau) had an error in the
evaluatin of the tail at last point, generating a problem when Ntau > Liw.
Fixed and checked.
NB: the evaluation of the density (G(tau=0-)) does not improve with Ntau,
but with Liw, provided by user. Best usage is Ntau=Liw.
libary moved into /opt
updated configuration files added more libraries (arpack,minpack,fftpack)
removed minpack from src/
updated Makefile and  tested compilation.
Merge branch 'devel'

Conflicts:
	lib/libscifor.a
	lib/libscifor_deb.a
	src/Makefile