Rails 4 support for multiparameter and date_time_select extensions

[emolayi]

Thank you for upgrading this gem for Rails 4. There is one piece that is missing that we are using in one of our apps. We have created a fork for our purposes that includes these commits: https://github.com/adzap/validates_timeliness/pull/101/files

Could you update your gem to include these changes?

[emolayi]

I am working on a PR to add support for the multiparameter and date_time_select extensions. The specs are passing in Rails 4.1.x, but failing using Rails 4.2. Since there have been so many changes in Rails 4.2, I feel that support for it should be part of a version bump in the validates_timeliness gem.