Using componentDidMount instead of componentWillMount

[kristofdombi]

The next major version of React is going to deprecate componentWillMount. Because of this, the next minor version (v16.3) is renaming componentWillMount to UNSAFE_componentWillMount.

I saw in the README, at the using FUIWR with local state section, that componentWillMount lifecycle method is used for listening to Firebase and setting local state.

I suggest that the README should support the use of componentDidMount method to be up to date for next version releases of React.

[kristofdombi]

I'd love to make a PR for this though, but before that, I just wanted to hear your opinions. 🙂

[nicolasgarnier]

Hey @kristof0425!

Yes that would work too :) Please send a PR, that would be awesome. Can you also change the example at the same time please?

Cheers!