tickets: #5373 and all its sub-tasks but #7740 ("Remove TrueCrypt").
This branch installs cryptsetup 1.6 from wheezy-backports, updates the
TrueCrypt wrapper to make the removal timeline clearer. All this can
be reviewed, and possibly merged.
It also contains a draft documentation for opening TrueCrypt volumes
with cryptsetup. sajolida, please review and improve as you see fit.
