v.5.31.0

Moderate BUG Fixes and development

DIFFEV
Improved the "diffev_best.mac" Macro.
The run_mpi lines are interpreted more carefully for the state of 'compute:';
Multiple 'run_mpi' lines are taken into account.

DISCUS
Added a possibility to dissolve molecules. The new "demolecularize" menu
allows to remove a molecule entry. The atoms that were in the molecule
retain everything except their molecule status.

surface menu
Small bug fix related to the accumulation of multiple planes.
Added a new optional parameter 'thick:thickness_value' that allows to
assign different thickness ranges in which atoms are turned into surface atoms.

domain menu
Small bug fix to check the headers of the input and content files more carefully