Add DomAttributes to typescript typedefs

[stephen-hopkins]

This resolves #151 by adding suggested React.DOMAttributes to Props interface. Allows use of onClick and other properties in typescript. No test added as it's an addition to type definitions only, ie non functional.

[robmadole]

@stephen-hopkins would React.HTMLAttributes be better?

[Rycochet]

It should be React.DOMAttributes<SVGSVGElement> to be absolutely correct (it's an <svg>...</svg> element, not a normal HTML element) - this does break mask in Props currently, but I'm not sure is FA is making use of the non-string properties added to the type.

[dangayle]

This one I think is better: #283

[robmadole]

I merged #283 and that has been released.