Handle new Vagrant base boxes gracefully

If there’s a new Vagrant base box for building Tails (like we had around Dec 23 2013, as shown by the new checksum in commit 89f8b20) there’s currently no mechanism to detect and deal with this. Users are left with a Vagrant setup based on the old base box without being informed of this, and will experience whatever issue that was the reason for updating the base box.

It’s demonstrated quite nicely by the current workaround user’s have to go through to rid themselves of the old stuff:

cd path/to/tails-sources/vagrant
# Delete the outdated vagrant machine
vagrant destroy -f
# Delete the cached, old base box so we'll download the new
# one that unfortunately is named the same...
vagrant box remove tails

One unfortunate thing is that there’s no notion of version for our base box currently. The actual base box file is named squeeze.box (always the same — only the checksum differs, but that doesn’t deal with the cache), and we don’t give an internal name (in Vagrant) so it’ll just be called default. We probably want to add a version number (perhaps we can use the creation date?) to both of these. This version should then be included in the Tails sources, indicating what is up-to-date. We’ll then compare these to automate something like the above workaround.

While we’re at it we can also switch the name from “squeeze” to “tails-builder” or something more descriptive.

Feature Branch: feature/vagrant-wheezy-basebox

Related issues

• Related to #7218 (closed)
• Has duplicate #6730 (closed)
• Blocked by #7643 (closed)

Original created by @anonym on 6736 (Redmine)