[views] new cubicweb logo (closes #3803681) - add the new CubicWeb logo - use it as a css (background-image) - change the color of the header bar (gradient made with css)

if 'same_as' in schema:
    sync_schema_props_perms('same_as', syncperms=False)
sync_schema_props_perms('Bookmark', syncperms=False)