Start adding schema migration into the release notes

* ``django.utils.unittest`` will be removed.

* ``django.db.models.signals.pre_syncdb`` and

  ``django.db.models.signals.post_syncdb`` will be removed, and

  ``django.db.models.signals.pre_migrate`` and

  ``django.db.models.signals.post_migrate`` will lose their

  ``create_models`` and ``created_models`` arguments.

2.0

---

What's new in Django 1.7

========================

Schema migrations

~~~~~~~~~~~~~~~~~

Django now has built-in support for schema migrations, which allows models

to be updated, changed and deleted and the changes stored into migration files

and then run on any deployed database.

Migrations are covered in :doc:`their own documentation</topics/migrations>`,

but a few of the key features are:

* ``syncdb`` has been deprecated and replaced by ``migrate``. Don't worry - 

   calls to ``syncdb`` will still work as before.

* A new ``makemigrations`` command provides an easy way to autodetect changes

  to your models and make migrations for them.

* :data:`~django.db.models.signals.post_syncdb` and

  :data:`~django.db.models.signals.post_syncdb` have been renamed to

  :data:`~django.db.models.signals.pre_migrate` and

  :data:`~django.db.models.signals.post_migrate` respectively. The

  ``create_models``/``created_models`` argument has also been deprecated.

* Routers something something.

Admin shortcuts support time zones

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