request, slapconfiguration: Add feature to define and get instance state.
(cherry picked from commit af181db0fb5ed7716e278745e3c9171e13b91dee)
request: use requester state as default state for the request

Default state for the requested instance should be the one of the requester
(cherry picked from commit 6c1fd542f991c74fbf10cb99bf7b09bb0e57ad93)
Add scalability test support
erp5: balancer: Fix maxconn get