robrix/Set — pull request #7 by IngmarStein (2014-10-04 15:06:22+00:00)
Title: Add minimumCapacity, remove ambiguous operator

This PR removes the + operator which is already provided by _ExtensibleCollectionType (SetTests.swift would not compile for me with Xcode 6.1 GM) and adds some methods from Dictionary (isEmpty, initializer with minimumCapacity).