Trying to view a video breaks stuff.

BROKEN (videos)

`http://mg.wandborg.se/u/joar/m/fluid-box-colourful/ <http://mg.wandborg.se/u/joar/m/fluid-box-colourful/>`_
`http://mg.wandborg.se/u/joar/m/new-deploy-test/ <http://mg.wandborg.se/u/joar/m/new-deploy-test/>`_
`http://mg.wandborg.se/u/joar/m/sintel/ <http://mg.wandborg.se/u/joar/m/sintel/>`_

WORKING (images)

`http://mg.wandborg.se/u/joar/m/photo-maj-09-8-06-07-em/ <http://mg.wandborg.se/u/joar/m/photo-maj-09-8-06-07-em/>`_
`http://mg.wandborg.se/u/joar/m/vasaparken/ <http://mg.wandborg.se/u/joar/m/vasaparken/>`_
`http://mg.wandborg.se/u/joar/m/4ec9534946102a5b6f00002c-tove/ <http://mg.wandborg.se/u/joar/m/4ec9534946102a5b6f00002c-tove/>`_

BACKTRACE

::

    File '/srv/mg.wandborg.se/mediagoblin/lib/python2.7/site-packages/Paste-1.7.5.1-py2.7.egg/paste/exceptions/errormiddleware.py', line 144 in __call__
      app_iter = self.application(environ, sr_checker)
    File '/srv/mg.wandborg.se/mediagoblin/lib/python2.7/site-packages/Paste-1.7.5.1-py2.7.egg/paste/urlmap.py', line 203 in __call__
      return app(environ, start_response)
    File '/srv/mg.wandborg.se/mediagoblin/lib/python2.7/site-packages/Beaker-1.6.1-py2.7.egg/beaker/middleware.py', line 155 in __call__
      return self.wrap_app(environ, session_start_response)
    File '/srv/mg.wandborg.se/mediagoblin/mediagoblin/app.py', line 158 in __call__
      return render_404(request)(environ, start_response)
    File '/srv/mg.wandborg.se/mediagoblin/mediagoblin/tools/response.py', line 33 in render_404
      request, 'mediagoblin/404.html', {}, status=400)
    File '/srv/mg.wandborg.se/mediagoblin/mediagoblin/tools/response.py', line 24 in render_to_response
      render_template(request, template, context),
    File '/srv/mg.wandborg.se/mediagoblin/mediagoblin/tools/template.py', line 82 in render_template
      context['csrf_token'] = render_csrf_form_token(request)
    File '/srv/mg.wandborg.se/mediagoblin/mediagoblin/meddleware/csrf.py', line 53 in render_csrf_form_token
      form = CsrfForm(csrf_token=request.environ['CSRF_TOKEN'])
    KeyError: 'CSRF_TOKEN'

BRANCH master

WORKING TREE STATE (latest commit)

::

    commit 72567762e36c849ffe8172b6cea4ca1be682e511
    Merge: a3663b4 ca9ebfe
    Author: Elrond <well@this-is-an-email-address.example.org>
    Date:   Mon Nov 28 18:40:45 2011 +0100
    
        Merge remote branch 'remotes/nyergler/issue-680-csrf-optout'
    
        * remotes/nyergler/issue-680-csrf-optout:
          Issue 680 Allow decorating views to prevent CSRF protection.
          Issue 680: Dispatch meddleware request processing post-routing

(this is to discuss this and then possibly implement it.
Implementing is **very** easy).

Currently jinja2 replaces ``{{ not_known }}`` by the empty string.
The question is, wether it would be better for it to throw an
error? Rationale being: Either it's a typo, or it's an error for
the variable to be referenced but not being there.

Does that make sense?

Enabling this:

::

    mediagoblin/tools/template.py:
    @@ -43,6 +43,7 @@ def get_jinja_env(template_loader, locale):
    
         template_env = jinja2.Environment(
             loader=template_loader, autoescape=True,
    +        undefined=jinja2.StrictUndefined,
             extensions=['jinja2.ext.i18n', 'jinja2.ext.autoescape'])

During unit tests nose imports every ``*.py`` it finds in the tree.
It does so to search for unit tests there. If the import fails,
this gives an error in the final unit test results.
For GMG this can fail, because some modules import optional
libraries (video for example).

Currently known options:


1. Add hard dependencies again for all optional libraries. Not
   nice, but would solve the problem at hand.
2. Rewrite the affected modules to somehow gracefully handle the
   situation and not error. Not really nice, but acceptable.
3. Change ``runtests.sh`` to call nose in a way, that tests are
   only searched in ``mediagoblin.tests``. This seems the nicest way.