This commit adds an `anon` class to the html tag when an anonymous user
visits a page. This allows elements to be appropriately hidden through
CSS alone.

The following things have been removed/cleaned up:
 * The `oae-anon-toggle` class for hiding the lhnav toggle
 * JS code related to hiding comment functionality
 * Trimpath code related to hiding comment functionality
 * A reference to the unused class `topnavigation-logged-out`