Duplicate extension while creating a new file

Document metadata are not correctly setted

While typing "title" as the document title in the creation form, we should have :

• dc title should be : "title"
• file name should be : "title.(ext)"

And with "title.(ext)"

• dc title should be the same as the file name.

It'is not currently the case. We have sometines : "filename.ext.ext".