TypeScript generation does not handle function overloads correctly

[dunhor]

E.g. all three of the following function get generated on a single class even though only the second one should be there (it is the one marked [default_overload])

        public contractDefaultOverloadV1(str: string, val: boolean): string;
        public contractDefaultOverloadV1(str: string, repeat: number): string;
        public contractDefaultOverloadV1(str: string, val: number): string;