[Housekeeping/General] Consider migrating to Typescript

[asvetliakov]

After supporting object spread: microsoft/TypeScript#2103

Pros:

• Easier refactoring
• No need to sync props with separate ts definition
• Easy to move on
• Completion in editor

Additional efforts

• Investigate and add support for TS types into react-docgen
• Remove react prop types from components?

[Asgator]

May use https://flowtype.org/ ?

This would make it more difficult to anyone not familiar with typescript to contribute. Whereas you can count on anyone using react to know js. You'd be looking at a lot less possible contributors.