mock20 types definition

Mock20 types definition file.

How to install?

npm i types-mock20 --save-dev

See https://www.npmjs.com/package/types-mock20

How to contribute?

1. Fork the repo
2. Do the changes
3. Test your changes
4. Add yourself to the contributors array in the package.json file.
5. Open a Pull Request

I'll try to merge the PRs as soon as possible.