Modernize code and update to support newer versions of RN without warnings.

[markrickert]

This PR does a few things to update the code and modernize the component.

This is the best component I've found for swiping rows in a Flatlist (all the other libraries make you style all the hidden elements yourself) so I wanted to stick with this library but it needed a little TLC to make it work with new versions of React since there are lots of deprecated lifecycle methods.

• I removed all binding functions in favor of property initializers. It's cleaner and there's less chance of memory leaks.
• I moved the creation of the PanResponder to the constructor method since componentDidMount is deprecated.
• Switch from the deprecated componentWillReceiveProps to componentDidUpdate
• Version 1.0.0 would only auto-close the SwipeRow when the property isOpen changed from true->false. I added a contition that allows you to animate the buttons open or closed so that <SwipeRow isOpen={true} /> will animate the row open if it is not.
• Added a note to stay at 1.0.0 if you're using React Native < 0.54.

I hope you like these changes and integrate them into this really useful and user-friendly library!