MarkUsProject/Markus — pull request #1393 by tiagochst (2014-03-15 17:26:38+00:00)
Title: Issue 1324 calendar

Removing vendor/plugin calendar-date-select and adding gem.
Fix one of the three DEPRECATION WARNING: "You have Rails 2.3-style plugins in vendor/plugins"

After the installation of the gem, a new step in the installation should be insert to install calendar javascripts in public folder: **`bundle exec rake calendar:install`**. Otherwise, it will not work.

Source:http://stackoverflow.com/questions/3979495/using-calendar-date-select-with-rails-3