Zend\View documentation improvement

I moved listeners into tables to improve readability and moved ``Zend\View`` from **broken** to **incomplete** in the TODO list. I'm not sure but I think the PR #707 fixed what was broke in the documentation, but it still needs documentation that is missing like ``Gravatar`` and ``Identity`` view helpers.

Update: I've also added a list of the view helpers with links to each one of them and added notes about *navigation* and *internationalization* view helpers.