Improve books/add-form, for existing works title not editable

When adding edition from an existing work, the title-field is locked. Especially for translations the titles differ from the original work so the should be editable. This can be changed in the next from, but in many cases the contributor may forget to change it then. It would be much easier if the title could be set in the first form.

### Describe the problem that you'd like solved
Make the title-fileld editable in the following form: https://openlibrary.org/books/add?work=/works/OLxxxW

### Proposal & Constraints
The field might refer to the works title when it should refer to the new editions title. It must be avoided that the works title will be changed from this form.