TEIID-4627 adds support for source level triggers to be called after CDC events.

The triggers are similar to what is supported by views, but "INSTEAD OF" is not supported - just AFTER.

CREATE TRIGGER name ON table AFTER (INSERT|UPDATE|DELETE) FOR EACH ROW statement

Just like view triggers new/old/changing values can be referenced. Note that unlike view triggers, these must be named as an arbitrary number of them are supported per table (like other of our constructs they are scoped to the table, not to the schema).

We may eventually want to support multiple event types for a single trigger and may need to support internal events as well.