Log Message:
py-psycopg2: updated to 2.8

Psycopg 2.8 released

After about two years from the previous major release, psycopg 2.8 is finally
here!

Among the highlights, PostgreSQL errors are now mapped to Python exceptions for
a more idiomatic way to handle them. Several additions allow a better insight
of the connection status and query results.

Behind the scene, asynchronous communication and concurrency received several
improvements, and dropping support for older versions of Python gave the chance
to refactor and modernise the codebase (with the especial help from Jon
Dufresne who ruthlessly butchered our code into a streamlined pulp).