Add a checkbox for the user to state he doesn't know the acceptance date
Other funder field updates

* Remove the other funder checkbox option
* Always show the other funder input field
* Replace the other funder input field with a textarea
Form addendum changes

* Remove the addendum checkboxes
* Move the addendum information to be displayed after the acceptance date field
Implement form content and copy updates
Remove unused translation keys
Sort the publicationform widget translation keys alphabetically