merge NIFTy_5

README.md

demos/bernoulli_demo.py

demos/getting_started_3.py

docs/source/code.rst

nifty5/data_objects/distributed_do.py

nifty5/data_objects/numpy_do.py

nifty5/field.py

nifty5/library/los_response.py

nifty5/linearization.py

nifty5/multi_field.py

nifty5/operators/operator.py

nifty5/sugar.py

test/test_energies/test_consistency.py

test/test_field.py

test/test_operators/test_operator_gradients.py