* Making the wakunode2 to support postgres driver
* driver/builder.nim: controling possible errors when creating the messages table
* postgres_driver.nim: adding protection in getInt and fixing typo
* Add postgres basic support
* test_driver_postgres.nim: adding simple test to validate asynchronous-ness
* Aligning the changes made by Andrea to the current master state
* test_driver_postgres.nim: new unit test (checking duplicate insertion)
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Co-authored-by: Andrea Maria Piana <andrea.maria.piana@gmail.com>