iZettle/izettle-toolbox — pull request #52 by oskarwiksten (2014-02-26 10:45:33+00:00)
Title: Generalize key type in SequenceGenerator

* The key type that is being used in `SequenceGenerator` does not necessarily have to be `String`.
* This commit changes it to being a parameterized type that the caller can specify.

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