feat(tblconv/sql): provide bulk sql writer

[Zaba505]

Just about all SQL queries for output are going to be INSERTs and currently, each record received from a source is applied to the query to fill in parameter placeholders and then that query is executed. This is obviously inefficient if there are lots of source records where instead of individually INSERTing every record a bulk insert would be much better.

NOTE: By bulk insert, I don't mean the SQL command BULK INSERT but instead supporting queries similar to the following:

INSERT INTO example
VALUES
  (100, 'Name 1', 'Value 1', 'Other 1'),
  (101, 'Name 2', 'Value 2', 'Other 2'),
  (102, 'Name 3', 'Value 3', 'Other 3'),
  (103, 'Name 4', 'Value 4', 'Other 4');

In the above example, 4 records would be read from the source and applied to the query to fill parameter placeholders. Thus, achieving a far more efficient bulk insert to the SQL output.