Merge branch 'mr_corrections' into 'NIFTy_5'

fixes

See merge request !284

README.md

@@ -122,7 +122,7 @@ dive into NIFTy by running one of the demonstrations, e.g.:
     python3 demos/getting_started_1.py
 
 
-### Acknowledgement
+### Acknowledgements
 
 Please acknowledge the use of NIFTy in your publication(s) by using a
 phrase such as the following:
@@ -133,7 +133,7 @@ phrase such as the following:
 and a citation to one of the [publications](http://ift.pages.mpcdf.de/NIFTy/citations.html).
 
 
-### Release Notes
+### Licensing terms
 
 The NIFTy package is licensed under the terms of the
 [GPLv3](https://www.gnu.org/licenses/gpl.html) and is distributed

docs/source/code.rst

@@ -402,7 +402,7 @@ Many minimizers for nonlinear problems can be characterized as
 
 This family of algorithms is encapsulated in NIFTy's
 :class:`~descent_minimizers.DescentMinimizer` class, which currently has three
-concrete implementations: :class:`~descent_minimizers.SteepestDescent`,
+generally usable concrete implementations:
 :class:`~descent_minimizers.NewtonCG`, :class:`~descent_minimizers.L_BFGS` and
 :class:`~descent_minimizers.VL_BFGS`. Of these algorithms, only
 :class:`~descent_minimizers.NewtonCG` requires the energy object to provide