remove future imports

bilby/__init__.py

bilby/core/__init__.py

bilby/core/grid.py

bilby/core/likelihood.py

bilby/core/prior/dict.py

bilby/core/result.py

bilby/core/sampler/base_sampler.py

bilby/core/sampler/cpnest.py

bilby/core/sampler/dynamic_dynesty.py

bilby/core/sampler/fake_sampler.py

bilby/core/sampler/nestle.py

bilby/core/sampler/polychord.py

bilby/core/sampler/ptemcee.py

bilby/core/sampler/ptmcmc.py

bilby/core/sampler/pymc3.py

bilby/core/sampler/ultranest.py

bilby/core/utils.py

bilby/gw/likelihood.py

bilby/gw/result.py

bilby/gw/sampler/__init__.py