Bug#795735: partman-crypto: always encrypt swap

[Lars Wirzenius <liw@liw.fi>]

Package: partman-crypto
Severity: wishlist
Tags: d-i

Could we enable encryption of swap by default, even when full disk
encryption is not used? As far as I undrestand, there is no
performance issue for this for most hardware made in the past
half-decade. Swap encryption also doesn't require the user to enter a
password: it can be generated on the fly for each boot.

This was suggested in the Debian GnuPG BoF at Debconf15.

-- System Information:
Debian Release: 8.1
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)

Kernel: Linux 3.16.0-4-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.UTF-8, LC_CTYPE=en_GB.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)