Add xmlns and other attributes to SVGAttributes

[mDibyo]

Please fill in this template.

• Prefer to make your PR against the types-2.0 branch.
• Test the change in your own code.
• Follow the advice from the readme.
• Avoid common mistakes.
• Run npm run lint -- package-name if a tslint.json is present.

If changing an existing definition:

• Provide a URL to documentation or source code which provides context for the suggested changes: <Add xmlns to svg attributes. react/react#6471>
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[dt-bot]

react/index.d.ts

to authors (@pspeter3 @vsiao @johnnyreilly AssureSign (account can't be detected) Microsoft (account can't be detected)). Could you review this PR?
👍 or 👎?

Checklist

• pass the Travis CI test?

[johnnyreilly]

Thanks!