[ts-gen] src, tag, ver -> table_name

[Ken Feng]

Hi Bill & Russ,

I am still investigating order responses.  I think 3|11|7 maps to
OrderReport which contains fill information, and it looks like 3|3|6
maps to OrderStatus, but I can't figure out what 3|5|10 is - it might
be OrderResult (position changes), but it also looks awfully close to
OrderStatus.

If the mapping between src, tag, ver and a MySQL table is one-to-one,
it would be great if there were a meta-table which has the four
columns src, tag, ver and tbl_name so we can just look it up in the
database.

It would be useful not only for a data-driven paradigm, but also for
documentation purposes; we could better understand the mapping between
the triplets and the tables.

- Ken