New functional / frontend test suite

Although CKAN has a pretty comprehensive testing of the backend (model, logic layer, auth, etc), the testing of the templates and controllers is very limited. Actually there are quite a number of functional tests, but they are based on the old Genshi templates so their relevance is limited.

There needs to be an effort to migrate these functional tests to the new templates (and the new tests structure). [Some tests](https://github.com/ckan/ckan/tree/master/ckan/new_tests/controllers) have already been written using [WebTest](http://webtest.readthedocs.org/en/latest/), but many more should follow.

We could also discuss using some tool like [Selenium](http://docs.seleniumhq.org/) to do browser-based testing.

Start by reviewing the existing functional tests based on the old Genshi templates and the tests in ckan/new_tests/controllers that use WebTest. Clarify whether the goal is migration to the new templates, adding broader controller and template coverage, or evaluating browser-based testing with Selenium. Done means an agreed scope and a substantially expanded, maintainable functional test suite.

Written by the indexing model from the issue text.