Add IntegrationTestCase.

* Lifted wholesale from another project.
Update changelog.
Update setup.py.
Improve access_view method.

* Add *args parameter.
* Clean up return statement.
* Also add a mention of view_class to the docstring.
Proper changelog/setup convention.
Expand access_assert_and_render() parameters.
Move error message construction out of assertEqual().
Use locals() for compactness.
Reorder parameters for syntactic correctness.
Merge branch 'master' into 18-integration-test-case

Conflicts:
	CHANGELOG.md
Merge pull request #18 from incuna/18-integration-test-case

Add IntegrationTestCase