Merge branch 'NIFTy_5' into misc_pa

nifty5/field.py

nifty5/library/adjust_variances.py

nifty5/library/correlated_fields.py

nifty5/library/dynamic_operator.py

nifty5/library/inverse_gamma_operator.py

nifty5/library/los_response.py

nifty5/library/smooth_linear_amplitude.py

nifty5/multi_field.py

nifty5/operators/block_diagonal_operator.py

nifty5/operators/chain_operator.py

nifty5/operators/contraction_operator.py

nifty5/operators/diagonal_operator.py

nifty5/operators/domain_tuple_field_inserter.py

nifty5/operators/endomorphic_operator.py

nifty5/operators/energy_operators.py

nifty5/operators/exp_transform.py

nifty5/operators/harmonic_operators.py

nifty5/operators/linear_interpolation.py

nifty5/operators/offset_operator.py

nifty5/operators/operator.py