UPDATE:

 - INTEGRATE: added a new interface to d_quadpack in a separate module. todo: add
a better interface using interpolating function.

 - added a script *create_portable.sh* which create a portable version of the scifor library with
an editable makefile. script needs a path to directory as only argument. A makefile entry
is created which run the script for a default directory DIR=./scifor_portable. To use it
$make portable [DIR=<your directory>]

 - PARSE_INPUT now use a linked lists and support comments for better use.

 - minor updated to CONSTANTS, ARRAYS, OPTIMIZE
UPDATE:

the installation and configuration of the SciFor library has been deeply updated.

The /etc/library.conf file contains different information now.
Lapack/Blas library are mandatory.
The presence of other available libraries is indicated through different boolean variables
which are used at compilation time of the library to set pre-compilation flags and
include or not routines or functions which use such libraries.

Other available libraries can be added to the system to ease coding, though these are
not strictly speaking necessary to compile SciFor.

- MINPACK in OPTIMIZE_ROOT_FINDING is now under pre-compilation flag
- QUADPACK has been completely removed (in src/.repo), new routines which
used QUADPACK ones will be subject to pre-compilation flag.

Other minor changes have been performed.
update & bugs fix:

bug: added variable in sfmake.inc containing path to scifor_completion script to simplify
construction of completion call in Makefile.
bug: found in sciforvars.sh script, "add_library_to_system *$*$LIB" double $-symbol in bash variable definition. fixed.
bug: in functions_bethe a problem appear in the gfbether routine, Hilbert transform of the bethe lattice on real-axis, because of
possible 1/0.0 case is w=0.0. Fixed by adding a small shift which prevents floating overflow.

update: in the process of updating the FFT module we introduced a better version of the DERIVATE module, which contains now
new routines to evaluate the 1,2,3,4,nth derivative using higher order formula (default=4, admitted are: [1 for n=1,2], 2, 4, 6)
Merge branch 'devel'

Conflicts:
	src/INTEGRATE.f90
	src/Makefile
	src/OPTIMIZE_ROOT_FINDING.f90
	src/create_portable.sh