Add SVG utility

[bennothommo]

This PR adds an SVG utility that can be used to extract and sanitize an SVG from a given path.

This class is a precursor to allowing full support for SVGs in Winter.

[github-actions]

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[github-actions]

This pull request will be closed and archived in 3 days, as there has been no activity in the last 60 days.
If this is still being worked on, please respond and we will re-open this pull request.
If this pull request is critical to your business, consider joining the Premium Support Program where a Service Level Agreement is offered.

[LukeTowers]

@bennothommo would this make more sense under the Winter\Storm\Parse namespace?

[bennothommo]

@LukeTowers it's not really a parser though. It's more a utility, like our Str or Arr utilities.

[LukeTowers]

@bennothommo can you add a PR to the docs for this?

[bennothommo]

@LukeTowers wintercms/docs#90