SciTools/iris — pull request #469 by bjlittle (2013-04-22 00:09:54+00:00)
Title: Gracefully merge cubes with different history.

The ```history``` entry within a cubes' ```attributes``` dictionary is often the first point of failure for two or more cubes to merge, simply due to time-stamp differences.

The PR gracefully merges cubes by ignoring the ```history``` attributes entry.