Merge branch 'NIFTy_5' into 'more_ift_docu_by_te'

README.md

demos/bernoulli_demo.py

demos/getting_started_2.py

demos/getting_started_3.py

demos/polynomial_fit.py

docs/source/code.rst

docs/source/conf.py

docs/source/ift.rst

docs/source/index.rst

docs/source/installation.rst

nifty5/__init__.py

nifty5/domains/domain.py

nifty5/fft.py

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