Do requests in the backgrounds off the back of redux-persist changes.

[Reisen]

Now that redux-persist can pull state from local storage, requests made by pages should be able to be a bit more intelligent. Particular ideas:

• Visiting an images page should automatically render the previous image results, and load new ones in the background but ONLY upon the first page and not a subsequent.
• Viewing an image should load only the metadata/tags, and not replace the image.
• Viewing the Upload page should use existing tags but pull all other tags in the background for competion.