[server] install custom sql scripts before creating tables for the schema
A cube might need something like 'CREATE EXTENSION postgis' before
creating tables for its entities, to add new final types.
if versions_map['cubicweb'][0] == (3, 7, 4):
config['http-session-time'] *= 60
config['cleanup-session-time'] *= 60
config['cleanup-anonymous-session-time'] *= 60