Removed deprecated custom season categorisation functions.
Remove docstrings from tests.
Fixed iris.util.array_equal to avoid issues with fully masked arrays
Update copyright dates
Force iris.tests to use TkAgg backend when called by idiff.py
Merge pull request #908 from dkillick/tkagg_in_idiff

Force iris.tests to use TkAgg backend when called by idiff.py
Revoked the deprecation of return values from callbacks.
pp 365 day cal

rev
test image permission

review changes

rebase and lines

date
Merge pull request #815 from marqh/testingImages2

test image permission
Review actions
Merge pull request #904 from rhattersley/remove-test-docstrings

Remove docstrings from tests.
Added @ajdawson's excellent observations.
Added the callback unit tests.
References to y now use self.y rather than self._interpolator.y
Updated copyright date to reflect the new year
Merge pull request #916 from dkillick/1d_extrap_yvals

Standardised interface to self.x and self.y in analysis.interpolate.Linear1dExtrapolator
Fix bug in comparison with netcdftime.datetime
Add PartialDateTime.__repr__ and update copyright periods.
Merge pull request #918 from rhattersley/fix-pdt-with-netcdftime

Fix bug in comparison with netcdftime.datetime