Remove TrueCrypt license to comply with DSFG standard

[frugalion]

So as Veracrypt is basically licensed with the TrueCrypt license, I think
it is better for Debian to not distribute such software, even in non-free.

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=814352
Also see #1682

The TrueCrypt compatibility is already dropped so Debian should be able to package this already.

cc:

• fjords@linuxmail.org
• n@sail.ng
• mike.gabriel@das-netzwerkteam.de
• invernomuto@paranoici.org
• 814352@bugs.debian.org
• eriberto@debian.org