Add GET method form handling

Add handling of forms for the GET method.  The code requires the form for
the GET method to be explicitly declared (e.g., get_form = AGetForm); the
form attribute will only be used for POST and PUT but not GET.
Avoid unbound form for GET instance

Do not attempt to get an unbound form for an instance using a GET
method.  This results in the same issue as getting a generic form where
an explicit form must be provided for an instance obtained using the GET
method.
Merge remote-tracking branch 'origin/Issue-140-master' into virtualenv-1
Merge remote-tracking branch 'origin/related-serializers-2' into virtualenv-1
Merge commit '11147ce13e754f47b9cdc8d0de8a071aa540882f' into virtualenv-1
Use the get_queryset from a resource if available

If a resource overrides the default get_queryset(), then
ModelMixin-based classes should use it instead of returning all objects
of the model of the resource.

The new order of returning a queryset is:
1. self._resource.get_queryset()
2. self.resource.queryset
3. self.resource.model.objects.all()
Merge commit '231b305' into virtualenv-1
Prevent instance corruption

Without a get_form in the view, it is possible for values to be reset
(True -> False) when the form defaults to OnTheFlyModelForm so skip the
GET method.  This alteration of the instance has a cascade effect since
DocumentingTemplateRenderer.render() will subsequently obtain put_form
and post_form using the altered instance.
Merge commit '59f927c' into virtualenv-1
Merge remote-tracking branch 'upstream/master' into virtualenv-1
Merge remote-tracking branch 'upstream/master' into virtualenv-1
Merge remote-tracking branch 'origin/master' into virtualenv-1
Merge remote-tracking branch 'origin/master' into virtualenv-1
Unicode causes a problem when serializing for example a dict with non-ASCII in the key. DRF attempts to first find an attribute with a name matching the key value. This fails with UnicodeEncodeError, which halts processing.

What is wanted is for DRF to continue looking for this field, it will find it in the dictionary, and serialize will succeed.
Merge branch 'virtualenv-1' of github.com:smartfile/django-rest-framework into virtualenv-1