Fix permissions
Bump ruby version
Allow dates to be formatted in error messages

Allows different formats for each type of object, e.g.:
en-GB:
  formats:
    date_validator:
      date_time: '%d %b %I:%M %p'
      time: '%I:%M %p'

Falls back to :default behaviour if no translation is found.
Merge pull request #1 from crmaxx/feature/mz-add-date-format

Allow dates to be formatted in error messages