Converts Travis CI tests to trusty64 with sudo
Converts Travis CI tests to trusty64 with sudo

The Travis CI tests have been running on legacy infrastructure. Indeed,
each and every Travis run reminds you:

   This job ran on our legacy infrastructure. Please read our docs on
   how to upgrade. [0]

We've been dragging our feet on the upgrade, because the new
Docker-based containers explicitly do not allow the use of sudo, which
is a hard requirement for our tests. But sudo-less Docker containers are
not our only option (praise the old gods and the new)! We also have the
option of using Ubuntu 14.04 LTS builds with sudo enabled [1], which is
a much better option for our use case, given that we explicitly support
14.04 for production instances, and our development VMs also run 14.04.

[0] https://docs.travis-ci.com/user/migrating-from-legacy
[1] https://docs.travis-ci.com/user/trusty-ci-environment/

mark-in/securedrop-prov-upstream,mark-in/securedrop-prov-upstream,mark-in/securedrop-prov-upstream,mark-in/securedrop-prov-upstream