Strip namespace from svg elements

[cjke]

SVG output from apps like https://www.sketchapp.com/ add namespaced attributes to svg elements. I believe these are generally useless for SVGs as a component, and React chokes on them:

Error output:

Module build failed: SyntaxError: Namespace tags are not supported. ReactJSX is not XML.

(I particularly like that last - its not XML!)

If you're cool with these coming out, I will do a PR

[goopscoop]

That's a good call. Cheeky React.

[osdiab]

According to the React docs xmlnsXlink is supported: https://facebook.github.io/react/docs/dom-elements.html

However, this is likely a responsiblity of the htmltojsx library at react-magic, as it is also being tracked in this PR: reactjs/react-magic#62