Add types for React4XP

[tajakobsen]

The types of the React4XP library ("/lib/enonic/react4xp") should be added to this package. See API Documentation for React4XP

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A good start could be the React4XP-types in the Mimir-project.

But the module needs to be declared the same way as all other modules in this project (see HttpLibrary as an example)

Code references to the new module also needs to be added to the following files:

• index.ts
• libs.ts
• Application list in: README.md