Merge branch 'master' into docs_spelling

* master:
  remove duplicate whats new entries from the last release (SciTools#3773)
  whatsnew latest update (SciTools#3771)

docs/iris/src/whatsnew/latest.rst

@@ -26,7 +26,7 @@ Features
 
 * The area weights used when performing area weighted regridding with 
   :class:`iris.analysis.AreaWeighted` are now cached.  This allows a 
-  significant speed up when regridding multiple similar cubes, by repeatedly 
+  significant speedup when regridding multiple similar cubes, by repeatedly 
   using a `'regridder' object <../iris/iris/analysis.html?highlight=regridder#iris.analysis.AreaWeighted.regridder>`_
   which you created first.
 
@@ -39,21 +39,7 @@ Features
 * Supporting Iris for both Python2 and Python3 resulted in pinning our 
   dependency on matplotlib at v2.x. Now that Python2 support has been dropped, 
   Iris is free to use the latest version of matplotlib.
-
-* The :class:`~iris.NameConstraint` provides richer name constraint matching 
-  when loading or extracting against cubes, by supporting a constraint against 
-  any combination of ``standard_name``, ``long_name``, NetCDF ``var_name`` 
-  and ``STASH`` from the attributes dictionary of a :class:`~iris.cube.Cube`.
-
-* Cubes and coordinates now have a new ``names`` property that contains a 
-  tuple of the ``standard_name``, ``long_name``, NetCDF ``var_name``, and 
-  ``STASH`` attributes metadata.
-
-* Name constraint matching against cubes during loading or extracting has been 
-  relaxed from strictly matching against the :meth:`~iris.cube.Cube.name`, to 
-  matching against either the ``standard_name``, ``long_name``,
-  NetCDF ``var_name``, or ``STASH`` attributes metadata of a cube.
-
+
 * CF Ancillary Variables are now supported in cubes.
 
 
@@ -134,12 +120,17 @@ Documentation
   formatter.  This is now automatically checked on GitHub PRs, replacing the 
   older, unittest-based "iris.tests.test_coding_standards.TestCodeFormat".
   Black provides automatic code format correction for most IDEs.  See the new 
-  developer guide section on :ref:`iris_code_format` 
+  developer guide section on :ref:`iris_code_format`.
 
 * Refreshed the :ref:`whats_new_contributions` for the :ref:`iris_whatsnew`.
   This includes always creating the ``latest`` what's new page so it appears
   on the latest documentation at
   https://scitools-iris.readthedocs.io/en/latest/whatsnew.  This resolves
-  :issue:`2104` and :issue:`3451`
-
+  :issue:`2104` and :issue:`3451`.  Also updated the 
+  :ref:`iris_development_releases_steps` to follow when making a release.
+
+* Enabled the pdf creation of the documentation on the `Read the Docs`_ service.
+  The pdf may be accessed by clicking on the version at the bottom of the side
+  bar, then selecting **pdf** from the downloads section.
 
+.. _Read the Docs: https://scitools-iris.readthedocs.io/en/latest/