setup.py: modified package psycopg2 to psycopg2-binary

[sangvo117]

I modified package psycopg2 to psycopg2-binary in setup.py to fix issue 477.

[spbnick]

Thanks a lot for the contribution! However, the official guidance from psycopg2 is that psycopg2-binary shouldn't be used in production, and psycopg2 should be used instead. I'll close this MR, but would love to see more contributions from you!