make sure celery doesn't prevent the main server to talk to the monitor while performing huge computes

fix setup-burp by enforcing burp2 backend for setup and fallback to client_version when we can't determine the server_version for the parser

Resolve "backport fixes from v0.6.2"

Closes #297

See merge request !110

Fix ldap

See merge request !102

Parallel for agent

See merge request !103

use a shared logger through a fabric in order to have the same settings everywhere

See merge request !101