relax SVN archive

The Dasha execute function has been updated to follow the lead of the Modelfree4 equivalent function
whereby a non-standary binary executable Dasha file can be specified.

The Dasha sample script has been significantly modified to optimise a series of model-free models.

The OpenDX surfaces have had their opacity levels changed to better veiw the curvature of the space.

The automatically generated Dasha script has been fixed. Previously the optimise command used was
'min all' or 'lmin all'. This is incorrect and the proper syntax is 'min m n' or 'lmin m n' where
m is the first residue number while n is the last.