(*) additional bug-fixes w.r.t. validation of the coefficients metadata:
(**) when adding a new task in index.html
(**) in "converger_1/controller.h" when checking the coeffs_at_once value w.r.t. set-size of grid-steps in a given, subsequent, complexity.

(*) more cleanish javascript code (new_task_type, as well as additional cleaning of the previously cleanish code w.r.t. the use of 'this.' -- now if it's public, it shall be declared via 'this.', local 'var'/'function' otherwise.

(*) regression bug-fix in the 'subsequent_complexity_type' (index.html) -- variables such as cli_coefficient_range_metadata_x and gui were missing... now localised, 'var' predicate.