* Deprecate usage of "quantity" float field in quantity_unit category
* Introduce Quantity Unit Conversion Module instead for this behavior:
     Quantity Unit Conversion Definitions can be used to define site-wide
     quantity_units
* Let Resources define their own children Definitions:
     - adds a new tab in Product view
     - the definitions defined at a Resource level override the "global"
       definitions made in the Units Module

* Definitions are indexed in a special catalog table, similarly to Measures.
* Add an interaction workflow to take care of two reindexation needs:
   - when a local (resource-level) Definition is modified/created, the Product
     itself needs to be reindexed. This step is quite similar to
     measure_interaction_workflow
   - when a global (site-wide) Definition is modified, all Products need
     reindexing.

* SimulationTool API was cleaned up and unified.
   - getConvertedInventoryList is deprecated
   - quantity_unit and metric_type parameters are added to getInventory

* testResource is updated to use Unit Definitions instead of quantity fields
  of quantity_unit's


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@31858 20353a03-c40f-0410-a6d1-a30d3c3de9de