Merge remote-tracking branch 'upstream/v1.7.x' into v1.8.x

* upstream/v1.7.x:
  Fix changed image for updated test environment.
  Update release date.
  Prepare v1.7.4
  Used concrete sized in shape for PP data proxy.
  More "what's new" for v1.7.4rc1
  What's new for v1.7.4.

Conflicts:
	docs/iris/src/whatsnew/1.7.rst
	lib/iris/__init__.py

docs/iris/src/whatsnew/1.7.rst

@@ -1,12 +1,12 @@
 What's new in Iris 1.7
 **********************
 
-:Release: 1.7.3
-:Date: 16th December 2014
-
 This document explains the new/changed features of Iris in version 1.7.
 (:doc:`View all changes <index>`.)
 
+:Release: 1.7.4
+:Date: 15th April 2015
+
 Iris 1.7 features
 =================
 
@@ -201,6 +201,17 @@ Bugs fixed in v1.7.3
 * Cubes that contain a pseudo-level coordinate can now be saved to PP.
 * Fixed a bug in the FieldsFile loader that prevented it always loading all available fields.
 
+Bugs fixed in v1.7.4
+^^^^^^^^^^^^^^^^^^^^
+* :meth:`Coord.guess_bounds` can now deal with circular coordinates.
+* :meth:`Coord.nearest_neighbour_index` can now work with descending bounds.
+* Passing `weights` to :meth:`Cube.rolling_window` no longer prevents other
+  keyword arguments from being passed to the aggregator.
+* Several minor fixes to allow use of Iris on Windows.
+* Made use of the new standard_parallels keyword in Cartopy's LambertConformal
+  projection (Cartopy v0.12). Older versions of Iris will not be able to
+  create LambertConformal coordinate systems with Cartopy >= 0.12.
+
 Incompatible changes
 ====================
 * Saving a cube with a STASH attribute to NetCDF now produces a variable