DarkCloud - SoundCloud Dark Mode

Changes soundcloud.com to a dark theme.

Turns Soundcloud.com into night mode, making it easier on the eyes. As a frequent Soundcloud user, I found the lack of a first-party 'night mode' strange. Thus, I have created one myself. I have tried to test as many pages and features as possible to ensure they work and look as intended, however I may have missed some. If this is the case, leave a ticket on GitHub (the "support website").