Did rough overall restructuring

bilby/gw/detector/__init__.py

bilby/gw/detector/detector.py

bilby/gw/detector/interferometer.py

bilby/gw/detector/networks.py

bilby/gw/detector/psd.py

bilby/gw/detector/strain_data.py

bilby/gw/likelihood.py

examples/injection_examples/australian_detector.py

examples/injection_examples/binary_neutron_star_example.py

examples/injection_examples/calibration_example.py

examples/injection_examples/change_sampled_parameters.py

examples/injection_examples/create_your_own_source_model.py

...tion_examples/create_your_own_time_domain_source_model.py

examples/injection_examples/custom_proposal_example.py

examples/injection_examples/eccentric_inspiral.py

examples/injection_examples/fake_sampler_example.py

examples/injection_examples/fast_tutorial.py

examples/injection_examples/how_to_specify_the_prior.py

examples/injection_examples/marginalized_likelihood.py

examples/injection_examples/non_tensor.py