Improve setting localized <title> of our documents

[jimporter]

There are a couple of ways we could improve how we set our <title>. Currently, as of #239, it takes a split second to fetch the localized title.

• Load our FTL files during webpack and pre-fetch the en-US localization for the title to inject into the template
• Inject our FTL files directly into the built HTML files so that we don't have to wait for a fetch to get the localizations. This also has the benefit of improving load time for our pages.