ZeroDivision error now captured correctly as fail against metadata.
Tidyup.
Review feedback.
rose date: isodatetime: initial attempt
rose date: implement ISO 8601 support
rose date: remove debugs from test
rose date: update documentation
Merge pull request #1202 from benfitzpatrick/rose.date.isodatetime

rose date: add ISO 8601 support
Update CHANGES.md
Update test.
Merge pull request #1196 from arjclark/rose-config.fix_divide_zero

fail-if: capture divide zero error