Merge pull request #625 from swistakm/master

Fix small mistake in docs.
Added @wronglink, for docs fixes in #592.  Thanks!
Merge pull request #624 from wronglink/fix_login_page

Login page styles fix. Closes #618. Made with :cookie:
Update release notes.
Ensure model field validation is performed for ModelSerializers with a custom restore_object method.  Fixes #623.
Update release notes
Update rest_framework/serializers.py
Added @swistakm, for docs fix #625. Thanks!
Merge pull request #629 from z4r/patch-1

Update rest_framework/serializers.py
Added @z4r. Thanks!

For ensuring `django-jsonfield` compatibility, via #629.
Docs tweaks.
Fix processing of ManyToManyField when it is empty

Signed-off-by: Fernando Rocha <fernandogrd@gmail.com>
Added regretion test for issue #632

Signed-off-by: Fernando Rocha <fernandogrd@gmail.com>
Merge pull request #632 from fernandogrd/master

Fix processing of ManyToManyField when it is empty
Use many=True style for pk relations.
Formatting fixes
Updated release notes.
Added @fernandogrd for bugfix #632.  Thanks!
Merge branch 'master' into many-fields

Conflicts:
	rest_framework/relations.py
Tweak empty list implementation