def pluralized_array_from_hash(hash, singular_key, plural_key)
      [].tap do |array|
        value = value_from_singular_key(hash, singular_key)
        value ||= value_from_plural_key(hash, plural_key)
        array << value
      end.flatten.compact
    end
def pluralized_array_from_hash(hash, singular_key, plural_key)
      [].tap do |array|
        value = value_from_singular_key(hash, singular_key)
        value ||= value_from_plural_key(hash, plural_key)
        array << value
      end.flatten.compact
    end
Read array from the supplied hash favouring the singular key
 and then the plural key, and handling any nil entries.

 hash - the hash to read from
 singular_key - the singular key
 plural_key - the plural key

 Returns an array