mongoid/mongoid — pull request #1958 by shingara (2012-04-27 12:13:25+00:00)
Title: Support for the :touch option in relations

This pull request add the `Document#touch` method with params to define which field you want touch. And the :touch option in belongs_to association to touch parent document if child document is touch.

This change is compatible to ActiveRecord API about touch (http://apidock.com/rails/ActiveRecord/Persistence/touch )

Can fix #1798