DjangoCMS 3.0 support and some missing FR translations

Hi Stefan,

When using cmsfiler_plugin_image with Django CMS 3.0, there is an Exception which is raised (see http://dpaste.com/hold/1554861/ ).
It's because page_link is not in "raw_id_fields" preventing the field to be wrapped with a RelatedFieldWidgetWrapper in django/contrib/admin/options, function formfield_for_dbfield (see https://github.com/django/django/blob/master/django/contrib/admin/options.py#L120 lines 156 to 162)

I added some missing FR translations too. I would like to make two different pull requests but I didn't find "how" in github...

Have a nice day.

--
Dylann
http://www.webu.coop