XD modifications and bug-fixes

Revision 2024.01 (XD2024) - released 2nd December 2024
                This version has an entirely revamped initialisation program XDINI,
                which automatically handles constraints for atoms in special positions
                and many other convenient features. See XDINI manual for a full list of
                the changes.
                
Revision 2023.01 (XD2016) - released 11th October 2023
                This is just a recompilation with larger atom arrays

Revision 2016.01 (XD2016) - released 8th July 2016

                Some new properties calculated in XDPROP including NCI and
                DORI. Windows GUI installation no longer requires any
                environment variable set by user (console version only
                requires TCL_LIBRARY). Ini files now stored in users %APPDATA%
                location for Windows version.

Revision 6.03 (XD2015) - released 31st July 2015

                Enhanced automatic-memory allocation and several new features 
                (in XDPROP). See XD2015 manual for details.

Revision 5.01c (XD2006) - released 8th October 2006

                Minor bug fixes in XDINI for SHELX input. Correction of
                Ueq calculated in XDLSM and XDGEOM.


Revision 5.00 (XD2006) - Released 4 October 2006

                Numerous new features have been added to XDPROP, and the new
                program XDPDF has been added. The new features are detailed
                in the program manual. A number of small, mainly cosmetic,
                changes to the program outputs.

Revision 4.10 - Released 24 July 2003
              
                A serious bug in XDFOUR and several minor bugs were fixed.

               (a) XDFOUR could give incorrect function values for non
                   centrosymmetric structures due to a fault in the sort
                   routine. Another bug in routine plotco, which caused a
                   segmentation fault for RedHat8.0 when using the *cryst
                   option without selected atoms was also fixed.
               (b) XDPROP - the *iam model only worked for the asymmetric unit.
               (c) XDPROP - the centre of mass was incorrectly computed when
                   symmetry related atoms were added.
               (d) XDFFT used to write an illegal CIF if no compid was given
                   on the command line.
               (e) a work-about for the failure of the hardcopy option in
                   XDGRAPH (OpenGL driver) for some Revisions of Linux is 
                   given in the program manual,available from this link.

Revision 4.09 - Released 23 May 2003