Created GPG Test key and allowed tests to run using this key instead of users key

I've edited the makefile to create a test GPG key and to
also create a "test" GPG home directory. This allows the
tests to be run using the test key instead of the users
key.
Python-gnupg 0.2.9 & Plinth are now downloaded and added
to build folder and scripts updated to include this path
in PYTHONPATH.

Python-routes,python-socksipy, python-cheetah & 
python-openssl are installed through makefile.