Adds commentary, keyboard navigation and useful info to the pages of Homestuck.com stories.
Homestuck Companion currently displays partial commentary for Homestuck (up to and including the Intermission), complete commentary for Problem Sleuth and enables keyboard navigation for both.
To use: just go to a supported URL like "https://www.homestuck.com/problem-sleuth/10" or "https://www.homestuck.com/story/513" and behold the commentary.
Keyboard controls work on every page of Problem Sleuth and Homestuck.
