Udpate project structure

README.md

jobs/src/__init__.py

jobs/tests/test_a_job.py

jobs/tests/test_bht_algorithm.py

jobs/tests/test_integrator.py

jobs/tests/test_jpl_data_query.py

jobs/unittests/__init__.py

tasks/tests/test_a_task.py

tasks/tests/test_direct_simulation.py

tasks/tests/test_ff_simulation.py