dillon1000/react

Add select event plugin

Polyfill 'onSelect' behavior for React.

Use non-standard 'selectionchange' event rather than 'select' event.
This allows us to fire the event when user moves the cursor via arrow
keys, and not just when they select multiple chars.

Add methods to ReactDOMSelection to make getting current selection
easier, so we can do a fast check for change without having to
calculate char offsets for selection start and end.