mathed compile failure

[Angus Leeming]

Thanks for the missing files, André.

Compiliation of mathed dies in MathCursor because a void function returns a 
value.

cxx: Error: math_cursor.C, line 1309: 
        #118 a void function may not return a value
                return niceInsert(new MathFuncInset(s.substr(1)));

Angus