Update card.rb
Update card.rb

card.save now includes "due" to approprately set the card's due date from an ISO8601 date.
CodingZeal/ruby-trello,ksamc/ruby-trello,danmcp/ruby-trello,jeremytregunna/ruby-trello,joneslee85/ruby-trello,gorenje/ruby-trello,brycemcd/ruby-trello,rossta/ruby-trello,playtestcloud/ruby-trello