Suggestion: Allow deep-linking for adding a source

[hazae41]

Hey, not an issue but rather a suggestion,

It would be great if we could make the user add a source by using deep-links like

altstore://sources/add?url=https://.../source.json

Or something similar, this would allow developers to make the user install a source without having to explain that he needs to copy some link, open AltStore, go to Sources, click Plus, and paste the link; he would just need to click the link and voila.

Thanks for the great work!