Inventory: Change the default inventory parameter for Inventory indexing.

Before:

default_inventory_calculation_list = ({"inventory_params" :
                                        {"node" : self.getDestination(),
                                         "group_by_sub_variation" : 1,
                                         "group_by_variation" : 1,
                                         "group_by_resource" : 1,
                                         }
                                         ..

After:

default_inventory_calculation_list = ({"inventory_params" :
                                       {"section": self.getDestinationSection(),
                                        "node" : self.getDestination(),
                                        "group_by_sub_variation" : 1,
                                        "group_by_variation" : 1,
                                        "group_by_resource" : 1,
                                         }
                                        ..

This is because Inventory_view of erp5_trade has both 'section' and 'node'
fields, so users can input both values, but due to the old default parameter,
the section will be ignored for inventory indexing. This is inconsitent.