Completion of task #3630 (https://gna.org/task/?3630).
The unmodified Hessian and turning the line search off are no longer both specified by the string
'None'. Now they are specified by the regular expressions '^[Nn]o [Ll]ine [Ss]earch$' and
'^[Nn]o [Hh]essian [Mm]od' respecively.
