Update Nuxeo 7.0 Mockups

Update Nuxeo 7.0 Mockups with latest remarks:

• Dashboard should display an activity stream
• The "view document" widget on summary (img, video, …) shouldn't allow to delete an asset already uploaded, only the update action.
• The search bar in header should be bigger (almost all the width), and display filters when arrow down.
• The tree should be visible and the 5.9.* styles should be updated
• Each content view should have a "sort by" on top of it
• The description is not useful by default
• The navigation should be only displayed in the left side blue bar, not in the header.