Feature: Datatype Retention

Handles the following Postgres datatype conversions and retention at sink.

uuid
date
jsonb
double precision
timestamp with time zone

Added case statements in PostgresSqlDatabaseDialect to retain the above datatype avoiding the default text to be streamed.
Added handling of date conversion in GenericDatabaseDialect to convert epoch value (number of days) to date.
This release helps the streaming tables to have required table structure.