[Spring] Fix spring controller validation

[cbornet]

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@bbdouglas (2017/07) @JFCote (2017/08) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01)

Description of the PR

The @Validated annotation is useless on models. At the same time, it must be set on the controllers to enable method parameters validation.

[macjohnny]

@cbornet great, I have always wondered why the parameter value constraints had no effect...