The default is to save them at ~/Mail, which isn't included in our
current Claws Mail persistence preset.

Tons of involved changes.

The $HOME files have been moved to /etc/skel in order to get rid of permissions
problems: we now let adduser deal with this.

New custom packages:
 - live-boot 2.0~a16-1+tails1.cb5e34 built from our Git repository. It
   integrates the changes our custom live-initramfs had.
 - live-config patched with xserver-xorg related fixes sent today on the Debian
   Live ML; hopefully this is only temporary...

- defaults to IMAP
- use SSL for IMAP and SMTP