Continued refactoring of output framework objects.

In this release, we cleaned up TableBuilder (it was too big).  In the
process, we created three new classes — Rows, Table, TitledComponent —
got rid off RowsBuilder, and modified Rows.  The design looks good,
although it will need more refinements.  We will take them up in later.

Details:
1. We broke up TableBuilder (it was big);
2. Now we have TableBuilder and Rows;
3. TableBuilder re-designed with columns and Rows;
4. In the process, we got rid off RowBuilder;
5. Row modified and leaned to fit the new design.
6. Id fitted with new method addTo(Row);
7. Now Id has two methods — addTo(Row), toRow(Row);
8. New object TitledComponent;
9. It helps avoid Law of Demeter violation in TableBuilder;
10. Also, with TitledComponent, client code cleaner;
11. We moved validation from Rows to Table;
12. Table extends Row and validates its row sizes.
13. Validation is now cleaner;
14. Other classes modified to fit the design.