Allow non-standard User models with Throttling

Use pk pseudo attribute for identifying the user (in case the user model is not the default and has a different column name for the unique id)

FIX: Don't default to list in method args

Prefetching the user object when getting the token in TokenAuthentication

Since the user object is fetched 4 lines after getting Token from the database, this removes a DB query for each token-authenticated request.

Fixes @list_route and @detail_route so that they don't initialize their `methods` parameter as a list. In some cases the list gets cleared, and the result is that default parameter is now empty, and may get reused unexpectedly.

Add django-rest-framework-recursive to docs

Small documentation fixes

* Remove "you you" from viewsets API-guide
* Fix link from routers API-guide to viewsets API-guide

Fixed missing whitespace in error string.

Fixed typos in docstrings

Update link for ember-django-adapter

Fix base_template examples 

_closable_objects as an empty list, not deleted

Cleanup '.model' shortcut from code and docs

Update filtering.md

Updated links for django-guardian package.

 ManyRelatedField.get_value clearing field on partial update

Use the proper db_table argument when constructing meta

Reload api_settings when using Django's 'override_settings'

Release notes for 3.0.4