Remove external dependency for Storybook

[campb303]

In storybook/DocsTheme.js, the brandImage is linked directly to a file on GitHub. This should be changed to support a local file if possible.

export default create({
  base: 'light',
  brandTitle: 'webqueue2 Front End Docs',
  brandUrl: 'https://engineering.purdue.edu/webqueue/webqueue2/build',
  brandImage: 'https://github.itap.purdue.edu/ECN/webqueue2-frontend/blob/master/public/logo192.png?raw=true',
  appBg: 'white'
});

[campb303]

Working on this.

[campb303]

It appears that the typical