Removing moderated edits

As per #1414 this WP will:

* Ignore the current column on the revisions table (although it is still set).
* Replace all the queries that are specifically looking at revisions (like package_list) and have them just query the package model instead (it'll be the same as the current=True revision).
* ~~_Eventually_ Remove the ability to view packages and other objects at specific revisions.~~

This PR no longer directly queries the *Revision objects in place of the original objects, there is no support for the pending state and so the latest revision should _always_ be the current revision.  This is a first step to making revisions configurable/removable.