Update react-d3-brush to be in sync with other projects.

[SPSpwetter]

See issue 34

Possibly just needs a version bump?

[SPSpwetter]

Ok, first off series isn't in react-d3-basic its in react-d3-shape.

From digging in, it seems that react-d3-brush is out of date with the other projects. Also, it is using some things that are no longer allowed in babel6 with regards to "export default".

[FilipPyrek]

How is it going? (still have same issue)

[SPSpwetter]

My co-worker added a brush component to the basic graph library, and is now one of the maintainers. So this project is probably defunct.

[vartika-skyport]

@FilipPyrek, I've introduced an independent Brush component in react-d3-shape library, you can use that.
Component: https://github.com/react-d3/react-d3-shape/blob/master/src/components/brush.jsx
Reference example: https://github.com/react-d3/react-d3-shape/blob/master/example/src/multi_line_brush.jsx