Initial commit for view-links-refactor branch.

The motivation behind these changes is the ability to add edit links
that are nested lists.  This allows us to add another dropdown to the
edit bar, from kotti.multilingual.

action_links has disappeared from type_info.  Needs b/w compatiblity.
Also, a usage example.
Minor changes to second tutorial (pep8 compliance,
mentioning template reloading)
Minor fix to second tutorial
Added third part of the tutorial, user interaction
Work around an issue with our event subscriber, which has problems cleaning things up.
Even though it is not PEP8 compliant, it should look like it
actually does. If it's fixed in the paster, we should also fix
it here.
Filter directly in the DB query, minor change to wording.
Filter directly in query.
Changed the wording to be more in line with the code
Fixed IndentationError and added a little more info
Merging latest changes.
Merge remote-tracking branch 'upstream/master' into review_tutorial_docs
Added my name to the CONTRIBUTORS.txt (forgot before)
Changed according to dnouri's comments, minor refactoring
and changed a few words around.
Merge branch 'review_tutorial_docs' of https://github.com/nightmarebadger/Kotti into review_tutorial_docs
Merge pull request #247 from nightmarebadger/review_tutorial_docs

Review and add to tutorials
Pin wsgi_intercept to 0.5.1.  This should fix tailing Travis tests.
Add missing dependency to pyramid_chameleon.
Add **kwargs to Node and Content constructors.
Merge branch 'master' into view-links-refactor
I no longer remember why we needed to take care of double event registrations.

But I'm sure it'll pop up soon.  Which is when we'll need to write a test
.