Refactor setup.py script
(cherry picked from commit a3b8bb52711537e1db8770bf447230f812b68166)
Txscapy is now in pypi, no need to have it mirrored on tpo
(cherry picked from commit e74ea0cbd7816bda547dced875523253ca6d312a)

Conflicts:
	requirements.txt
Update setup.py script and test that it works.
(cherry picked from commit 7a55afa0399d2338f6ac5b8e2232e3645d694c06)
Merge branch 'test/hellais/feature/setup.py' into develop