DEV: update custom dynesty proposals

bilby/core/sampler/dynesty.py

bilby/core/sampler/dynesty_utils.py

docs/dynesty-guide.txt

docs/images/stats-plot.png

examples/core_examples/hyper_parameter_example.py

examples/tutorials/compare_samplers.ipynb

requirements.txt

test/core/sampler/dynamic_dynesty_test.py

test/core/sampler/dynesty_test.py

test/integration/sampler_run_test.py