PIM-3298 : in product edit, don't display a value with a locale specific attribute

 - [x] edit form
 - [x] specs
 - [x] mass edit
 - [x] behats

| Q                    | A
| -------------------- | ---
| Bug fix?             | Y
| New feature?         | N
| BC breaks?           | N
| CI currently passes? | Y
| Tests pass?          | Y
| Scenarios pass?      | ?
| Checkstyle issues?*  | N
| PMD issues?**        | N
| Changelog updated?   | Y
| Fixed tickets        | PIM-3298
| DB schema updated?   |
| Migration script?    |
| Doc PR               |
2014 now, 2015 soon, be ready