Merge branch 'release/1.1.0'

* release/1.1.0:
Bump version number.
Properly support deferred fields...probably.
Add more Django versions to Travis.
Add `update_together` test.
Documentation fixes.
Update documentation.
Handle required ForeignKey DoesNotExist errors gracefully
Add a failing test for the foreignkey assignment issue
Add whitespace.
Support Py3's new metaclass syntax.
Change UpdateTogether mixin to UpdateTogetherModel
Initial update_together attempt.
Merge branch 'master' of https://github.com/karanlyons/django-save-the-change

# By Jon Bolt
# Via Jon Bolt
* 'master' of https://github.com/epicbagel/django-save-the-change:
  Handle null foreign key values

Conflicts:
	save_the_change/mixins.py