The assignment:
There are several different ways this could be done. The basic task is to allow the user to view some of the code in the file, select the correct line, and the line as it should properly appear. The most important thing be the the UI be intuitive, warn the user of the inherent danger of editing files, and try to keep the complexity to a minimum. phpBB 2.2 has does have some file editing features that you may want to mirror. Don't worry about the actual file i/o associated with writing the file, I will handle that. Just worry about how the user will pick the line and make the edit. I will take it from there.
I would have to say that this would be a job for a single developer. Discussion on how to implement should probably take place before someone actually attempts it. I do understand that there is a risk that a user could screw up their board so no need to debate this. The user will be sufficiently warned and if they decide to pull the trigger, then that's their decision.
Good luck!
-Nuttzy
