!6 rebased and in a big
commit so that we can start using that
SimulationTool: implement "linear" flow API

testInventoryAPI: silent pyflakes warnings

more interpolation implementation

inventory_list interpolation flow: support at_date & to_date

more and more interpolation API

interpolation

interpolation

group_by_time_sequence_list

testInventoryAPI: move inventory valuation methods in a dedicated test class

This should not be in test inventory list.

test: move Tracking API to a dedicated test module

inventory api: dirty way of disabling cache if keys such as node_category are used.

interpolation: security on SimulationTool_zGetInterpolationMethod

SimulationTool_zGetInterpolationMethod is called in restricted context
of Resource_zGetMovementHistoryList so it needs to be usable by
anonymous.

ZSQL Method does not read parameters from REQUEST, so it looks safe.

inventory_api: rely on catalog to add slot_index in the query

instead of implementing this logic in ZSQL's DTML