Add missing return statement.

docs.settings: fix name of `VERSION_PARAM`

Fix #4272.

Fix Typo in index.md

Currently generating invalid URL at index page.
http://www.django-rest-framework.org/'api-guide/schemas.md'

Though it is correct in navigation.

Changed http://example.com/api/items/4/.json to http://example.com/api/items/4.json

* 3.4.0 Release

* Version 3.4 release

* Full release notes

* Update translation files

* Update release documentation

* Update release notes

* Docs on supporting alternate schema formats

* Add schema_renderers to DefaultRouter

* lookup_type is deprecated in favor of lookup_expr
* assertEquals is deprecated in favor of assertEqual
* app_name is a required keyword as of Django 1.10

Add `localize` keyword argument for DecimalField

Fix setup.py error on some platforms

* Added schema generation support.
* New tutorial section.
* API guide on schema generation.
* Topic guide on API clients.

Update pagination.md

Added missing colon in extra_kwargs documentation

Add Sentry as a premium sponsor.

It is possible that a key in a MultiValueDict has multiple values, lists
are represented this way. When accessing a key in a MultiValueDict
it only returns the last element of that key. This becomes a problem
when parsing an html dict with a list inside of it.

To fix this problem we have to get and set the value using .getlist()
and .setlist().