ENH: Stash code to field code translation table.
MAINT: Changes based on review.
Review actions
Fix iris.util.rolling_window for degenerate masks.
Merge pull request #948 from cpelley/stash_fieldcode

ENH: Stash code to fieldcode translation
Merge pull request #961 from rhattersley/fix-rolling-window-degenerate-mask

Fix iris.util.rolling_window for degenerate masks.
ENH: Nearest neighbour regrid adds crs.

This adds the crs to the target grid if possible (is an iris coordinate
system).  There are also various documentation tweaks as part of this.
MAINT: Review actions taken