Add Wagtail CMS for kfet app.

K-Fêt
- Integrate wagtail to serve "static" pages of old K-Fêt website
- Fixture "kfetcms/kfet_wagtail_17_05" contains a copy of old website
(as in May 2017).
- Media files can be got until end of June 17 at
http://partage.eleves.ens.fr//files/604e6dea2ceebc66b1936c6b3f911744/kfet_media.tar.gz

Login/logout
- Update package django_cas_ng to last version.
- Clean COFCASBackend.
- Change CAS version to 3 (version used on eleves.ens). This enables
the logout redirection (for CAS ofc).
- Add messages and clean existing ones on login/logout (for both
outsider and cas users).

Misc
- Update settings to bypass an incompability between debug-toolbar and
wagtailmenus packages.
- Better management of dev/test-specific urls (if debug-toolbar wasn't in
INSTALLED_APPS, media files were not served).
- UI improvements.

kfet/cms/migrations/0001_initial.py

@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import modelcluster.fields
+import wagtail.wagtailcore.fields
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('wagtailcore', '0033_remove_golive_expiry_help_text'),
+        ('wagtailimages', '0019_delete_filter'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='GroupTeam',
+            fields=[
+                ('id', models.AutoField(primary_key=True, verbose_name='ID', auto_created=True, serialize=False)),
+                ('name', models.CharField(max_length=255, verbose_name='Nom')),
+            ],
+            options={
+                'verbose_name': 'Groupe de K-Fêt-eux-ses',
+                'verbose_name_plural': 'Groupes de K-Fêt-eux-ses',
+            },
+        ),
+        migrations.CreateModel(
+            name='KFetPage',
+            fields=[
+                ('page_ptr', models.OneToOneField(primary_key=True, to='wagtailcore.Page', parent_link=True, auto_created=True, serialize=False)),
+                ('no_header', models.BooleanField(verbose_name='Sans en-tête', help_text="Coché, l'en-tête (avec le titre) de la page n'est pas affiché.", default=False)),
+                ('content', wagtail.wagtailcore.fields.RichTextField(verbose_name='Contenu')),
+                ('custom_template', models.CharField(max_length=255, verbose_name='Template personnalisé', blank=True)),
+            ],
+            options={
+                'verbose_name': 'page K-Fêt',
+                'verbose_name_plural': 'pages K-Fêt',
+            },
+            bases=('wagtailcore.page',),
+        ),
+        migrations.CreateModel(
+            name='KFetPageGroupTeam',
+            fields=[
+                ('id', models.AutoField(primary_key=True, verbose_name='ID', auto_created=True, serialize=False)),
+                ('sort_order', models.IntegerField(editable=False, null=True, blank=True)),
+                ('title', models.CharField(max_length=255, verbose_name='Titre du groupe', blank=True)),
+                ('content', wagtail.wagtailcore.fields.RichTextField(verbose_name='Texte de présentation du groupe')),
+                ('group', models.ForeignKey(related_name='+', verbose_name='Groupe de K-Fêt-eux-ses', to='kfetcms.GroupTeam')),
+                ('page', modelcluster.fields.ParentalKey(related_name='team_groups', to='kfetcms.KFetPage')),
+                ('show_only', models.IntegerField(default=None, verbose_name='Montrer seulement', blank=True, null=True, help_text='Nombre de membres du groupe affichés initialement. Laisser vide pour tou-te-s les afficher.')),
+
+            ],
+            options={
+                'abstract': False,
+                'ordering': ['sort_order'],
+            },
+        ),
+        migrations.CreateModel(
+            name='MemberTeam',
+            fields=[
+                ('id', models.AutoField(primary_key=True, verbose_name='ID', auto_created=True, serialize=False)),
+                ('sort_order', models.IntegerField(editable=False, null=True, blank=True)),
+                ('first_name', models.CharField(max_length=255, verbose_name='Prénom', blank=True, default='')),
+                ('last_name', models.CharField(max_length=255, verbose_name='Nom', blank=True, default='')),
+                ('nick_name', models.CharField(max_length=255, verbose_name='Alias', blank=True, default='')),
+                ('group', modelcluster.fields.ParentalKey(related_name='members', verbose_name='Groupe de K-Fêt-eux-ses', to='kfetcms.GroupTeam')),
+                ('photo', models.ForeignKey(related_name='+', on_delete=django.db.models.deletion.SET_NULL, blank=True, verbose_name='Photo', to='wagtailimages.Image', null=True)),
+            ],
+            options={
+                'verbose_name': 'K-Fêt-eux-se',
+            },
+        ),
+    ]