convert Person to ES6 (#81)
convert Person to ES6 (#81)

* refactored Person.js to extend React.Component instead of React.createClass()

React.createClass is deprecated in React 15.5.0. Person has state, so it isn't eligible to become a functional component. In the meantime, convert it to use regular ES6 classes.

* whitespace consistency: 4 spaces
mjec/rc-niceties,mjec/rc-niceties,mjec/rc-niceties