Remove appliance script to install lts kernel from backports.
Fix lintian warning in package description.

W: globaleaks: description-synopsis-starts-with-article
Refine packer scripts.

* Do not download vagrant public key from random places on the internet, but use
  the one stored locally.
* Do not keep the output directory of the vagrant build.
* Give a proper name to the vagrant box;
* Add a not about the use of storm 0.20 in scripts.
Fix lintian error "no-copyright-file".

E: globaleaks: no-copyright-file
Fix lintian warning "debian-changelog-has-wrong-weekday".

W: globaleaks: debian-changelog-has-wrong-weekday 2014-09-24 is a Wednesday
Remove backend/script/glclient-build.

This script is not needed anymore (not that it was really useful before..)
Fixes lintian warning:
W: globaleaks: binary-without-manpage usr/bin/glclient-build