Rewrite the Views contextual links implementation to fix a number of bugs and...

Rewrite the Views contextual links implementation to fix a number of bugs and user experience issues, and to make it more flexible.

This patch is up for review at http://drupal.org/node/876772#comment-4125508 and could undergo changes as a result of that, but I am committing it
here so it we can test and develop against it.