SciTools/iris — pull request #190 by bjlittle (2012-11-07 12:09:00+00:00)
Title: Remove redundant and erroneous standard_name to LBFC/STASH PP save rules.

Working with AQUM revealed that loading a Fieldsfile with a PP-field of ```stash code 2``` is translated to a cube with ```standard_name``` of ```eastward_wind```, and that a PP-field of ```stash code 3``` is translated to a cube with ```standard_name``` of ```northward_wind```.

On saving such cubes, the PP save rules set/clobber the ```LBFC``` and ```LBUSER[3]``` (stash section and item) based ```only``` on the ```standard_name``` of the cube:
* For ```eastward_wind``` it forces ```56``` and ```15201```,
* For ```northward_wind``` it forces ```57``` and ```15202```.

These PP save rules are clearly wrong. It is not safe to translate from ```standard_name``` to ```stash code```.

These save rules have been removed, along with several others. All test still pass after removal, so thankfully we don't have current tests that rely on this erroneous behaviour.