Add media by URL, from various sources

[JakobKallin]

For scenarios where users cannot easily add media to their Google Drive, being able to add media directly from a URL would be convenient. The URL could be parsed and then automatically processed if the given source is supported. Examples of sources that could be supported are YouTube and SoundCloud.

One challenge is to manage the technical limitations of the various APIs (or embeds). Another potential problem is the licensing restrictions for importing or embedding content.