massive reworking

demos/bernoulli_demo.py

nifty5/domain_tuple.py

nifty5/extra/energy_and_model_tests.py

nifty5/field.py

nifty5/library/correlated_fields.py

nifty5/linearization.py

nifty5/multi_domain.py

nifty5/multi_field.py

nifty5/operators/block_diagonal_operator.py

nifty5/operators/chain_operator.py

nifty5/operators/diagonal_operator.py

nifty5/operators/endomorphic_operator.py

nifty5/operators/energy_operators.py

nifty5/operators/linear_operator.py

nifty5/operators/operator.py

nifty5/operators/relaxed_sum_operator.py

nifty5/operators/simple_linear_operators.py

nifty5/operators/symmetrizing_operator.py

nifty5/sugar.py