test serializers: update to rest framework 3.0

Signed-off-by: Cleber Rosa <crosa@redhat.com>
Job methods: remove testcount and passrate APIs for reimplementation

Signed-off-by: Cleber Rosa <crosa@redhat.com>
Views: update to use detail_route decorator and method syntax

Signed-off-by: Cleber Rosa <crosa@redhat.com>
requirements.txt: sync with update requirements

That is, Django Rest Framework >= 3.0 and nested routers 0.9.0.

Signed-off-by: Cleber Rosa <crosa@redhat.com>
API functional test: add HTTP status check to get()

Signed-off-by: Cleber Rosa <crosa@redhat.com>
API functional test: add HTTP status check to post()

Signed-off-by: Cleber Rosa <crosa@redhat.com>
API functional test: add test for /jobstatuses/

Signed-off-by: Cleber Rosa <crosa@redhat.com>
API Functional test: add test for /teststatuses/

Signed-off-by: Cleber Rosa <crosa@redhat.com>
API functional test: add test for /jobstatuses/ post

Signed-off-by: Cleber Rosa <crosa@redhat.com>
API functional test: add test for /teststatuses/ post

Signed-off-by: Cleber Rosa <crosa@redhat.com>
API functional test: get() already checks status

Signed-off-by: Cleber Rosa <crosa@redhat.com>