Remove online dependencies

[sethfitz]

Spotted so far:

• Roboto (Google Fonts) in Component export #54
• Intl polyfill
• resizer.digital-democracy.org
• Mapbox style mapbox://styles/gmaclennan/cio7mcryg0015akm9b6wur5ic
• Vector tiles (source defined in style)

[gmaclennan]

Intl polyfill is only needed in Safari, and since #54 is only an implementation detail and not part of the export.

resizer.digital-democracy.org is used to keep bandwidth down when online by dynamically resizing images. It also helps with browser memory though when rendering the image grid view. Could bundle https://github.com/digidem/vips-resizer in the electron app, but let's not prioritize for now and just render full-sized images direct from the hyperdrive media store that @substack is working on.