added data dumper util in order to debug globaleaks data structures
Upgrade requirement `cryptography` to 0.5.
Use setuptools instead of distutils in setup.py.

Among the other things, developers are now allowed to install globaleaks into
develop mode with::
$ python setup.py develop
Happy hacking.
Optimize setup.py with trivial corrections.

* Use for line in file, not readlines(), unless you do want to read the whole
  file at once;
* Use listcomp, as we want to return a list, not a map object.
* Tune indentation.
Merge branch 'devel' of github.com:globaleaks/GLBackend into devel