Prepare library to work with react 17.

[aleksuk]

Library uses componentWillUpdate life cycle hook which is deprecated and will be removed in the react@17.

Warning: componentWillUpdate has been renamed, and is not recommended for use. See https://fb.me/react-unsafe-component-lifecycles for details.

* Move data fetching code or side effects to componentDidUpdate.
* Rename componentWillUpdate to UNSAFE_componentWillUpdate to suppress this warning in non-strict mode. In React 17.x, only the UNSAFE_ name will work. To rename all deprecated lifecycles to their new names, you can run `npx react-codemod rename-unsafe-lifecycles` in your project source folder.

Please update the following components: TagsInput

[fjaguero]

Thanks for the report @aleksuk. I will have a look.