tests/test_nanshe_learner.py: Provided support for drmaa tests in TestNansheLearner.setup.
tests/test_nanshe_learner.py: Added a test for generate_neurons_blocks that uses DRMAA.
tests/test_nanshe_learner.py: Added a test for generate_neurons_io_handler that uses DRMAA.
tests/test_nanshe_learner.py: Added a test for main that uses DRMAA. This fixes #137.