PIM-1813 : rename product attribute
PIM-1813 : rename product attribute translation
PIM-1813 : rename product attribute validator
PIM-1813 : rename product attribute classes and references
PIM-1813 : rename product attribute classes and references
PIM-1813 : update fixtures context
Update changelog
Merge pull request #635 from akeneo/refactor/rename_product_attribute

[WIP] Refactor/rename product attribute
Rename routing file
Update attribute controller service id
Update attribute class parameter name
Update attribute option and attribute option value class parameter names
Update attribute manager service id
Update form-related service ids and form aliases
Update attribute datagrid name
Update routing
Update attribute related routing and controller actions
Update attribute acl labels
Update attribute page titles and references in docblocks
Update column name and tests