[IMP] web: 'Not Archived' becomes 'Active', 'Not published' becomes 'Unpublished'

Another reason why it’s better to change ‘not archived’ into ‘active’ is
because ‘active’ is the functional name of this field in the filter list in list view.

For the rest, it’s just a better en_US way of saying it.

addons/website_event_track/views/website_event_track_templates.xml

@@ -126,7 +126,7 @@
                 <div class="col-sm-10">
                     <h3 class="mt0 mb0">
                         <a t-attf-href="/event/#{ slug(event) }/track/#{ slug(track) }"><span t-field="track.name"> </span></a>
-                        <small t-if="not track.website_published" class="label label-danger">not published</small>
+                        <small t-if="not track.website_published" class="label label-danger">unpublished</small>
                     </h3>
                     <ul class="list-inline mb0">
                         <li t-if="track.speaker_ids" class="text-muted fa fa-user">