Add vuito

[mathix420]

Checklist:

• [x] I've read and understood Contributing Guidelines.
• [x] I've added the new resource at the end of its section.
• [x] This resource is ~~out there for a while~~, and actively maintained.
• [ ] This resource is popular enough and has at least a few hundred stars on GitHub.

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Vuito is the only isomorphic validation library out there and since it's also template-based you can easily share your validations between your back and frontend with it. By so having a fully secure data validation.

I know that it does not fit all the requirements of the checklist, but I truly think this library can help a bunch of people. It's well maintained, super-lightweight, and has great codeclimate grades. However, feel free to close this PR if you think vuito does not belong here.

Have a nice day!