Add Enumerable#uniq?

Imported from Lighthouse. Original ticket at: http://rails.lighthouseapp.com/projects/8994/tickets/6588 Created by Bounga - 2011-03-16 11:17:03 UTC

Checks for Enumerable content uniqueness

Returns true if the collection has no duplicated content. Can be called with a block too, much like any?, so people.uniq? { |p| p.age > 26 } returns true if only 1 person is over 26.

Unit test are included.

Please test and +1 this useful tiny patch.