Add advanced generic and wild-card parse mechanism

[amakaroff]

Hello!
We use your library for generating random values for our model. Our model has difficult generic and easy-random can't determinate some generic and skipped it. But we require fill all models by non null or empty values. So we decided to fix it in easy-random
From our side, it's look like a fix, but changes a little large :)
We understand about maintenance mode in easy-random, but I hope our changes will accepted like fix. In otherwise we will have to fork it. But we don't want to create our fork. I add that changes by flag, so current behavior not changed.

Thank you for library!

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[prenevin]

Excited for this merge