[IMP] rename_models: Handle properties that reference to the old model
[IMP] rename_models: Handle properties that reference to the old model

Use case: You are renaming from model A to model B, and there are
a many2one company dependent (property) field whose relation is model
A. The field "value_reference" of these properties are of the form
'A,<id>'. We have to change them to 'B,<id>'.

OCA/openupgradelib