Fix deletenodethread not existing
Remove debug print
Retrieve SFTP key from python
test-requirements.txt + workaround nodepool dep.

Added a proper test-requirements.txt to set up all the test dependencies
in one go. To avoid the need for the nodepool, the import has been moved
to the inside of the class.
Merge pull request #7 from matelakat/add-test-requirements

test-requirements.txt + workaround nodepool dep.
Intial commit for job and job repository
Added sqlalchemy as a test dependency