Fix homepage and invite tests

Fix #39
Upgrade to Django 1.7
Hardcode User modal class

in order to avoir an AppRegistryNotReady error
as described at
https://docs.djangoproject.com/en/1.7/ref/applications/#troubleshooting
Remove references to pinax.apps.blog
Pin django-compressor version
Upgrade django-auth-ldap
Uprade Track model imports
Don't use outdated depth option
Fix messages app naming clash
Set default value for boolean fields
Set test runner to silence warning 1_6.W001
Fix blog app
Remove fixture that break tests
Rename get_query_set to get_queryset
Fix warning about XViewMiddleware

XViewMiddleware has been moved to django.contrib.admindocs.middleware
Add field attribute do MessageAdminForm

Fixes deprecation warning :

Creating a ModelForm without either the 'fields' attribute or the
'exclude' attribute is deprecated - form MessageAdminForm needs updating
Copy django-tagging into the project source tree

This package is not longer maintained. I needed to update it for Django
1.7.
Use the cycle from the future tag library

Fixes warning:

RemovedInDjango18Warning: 'The `cycle` template tag is changing to
escape its arguments; the non-autoescaping version is deprecated. Load
it from the `future` tag library to start using the new behavior.
Add missing dependencies
Update WSGI script for Django 1.7

Fix #37