Update readme, fix previous mistakes, add viewBox to generated svgs.

[CallumNZ]

Proposed Changes

This update was initiated simply to add the viewBox attribute to the generated SVGs, so that they can be resized by downstream users. Other changes were made to hopefully reduce confusion the next time someone edits this package, and needs to regenerate the SVGs.

Production Changes

The following production changes are required to deploy these changes:

• None

Review

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Code Review Guide

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