SciTools/iris — pull request #1384 by pelson (2014-10-10 10:21:15+00:00)
Title: Preserve the datatype of time arrays converted with Unit.

The symptom was that people have been using ``iris.util.unify_time_units`` to unify their 360_day calendar epochs and the resulting cubes wouldn't merge/concatenate due to the data type being different.