Encrypted Home Directory Offered to All Users

The Encrypted Home Directory option is currently only available in the alternate installer, or on the desktop installer *with a preseed option* (user-setup/encrypt-home=true).

This was pulled from the Jaunty desktop installer due to a few minor usability concerns. This Blueprint suggests that we define those concerns now, and show this option in the Karmic desktop installer.

Discussion Points:
 * security: need encrypted swap space (see ecryptfs-setup-swap), need to be able to resume from hibernation to encrypted swap
 * usability: need a very clean mechanism for getting the user to record their randomly generated passphrase (currently implementation is passable, but could be improved)
 * usability: need a couple of graphic utilities for managing some options (see other blueprint for Jaunty, ecryptfs-ui)
 * migration: would be nice to offer a migration utility for enabling/disabling encrypted-home after installation
 * security: create a 700 ~/Private directory for all users. expose an easy option to set this up for encryption (if home is not already encrypted). ensure that ~/Private is translatable (xdg-user-dirs?)
 * install ecryptfs-utils by default on all ubuntu servers and desktops, such that users can run ecryptfs-setup-private and at least setup a secure private space at any point after installation
 * ... anything else?

:-Dustin