Idea Only : looking at testing

- If PHPUnit is on the cards for testing, it's not going to play nicely when setting content type headers unless each test is run in process isolation.  Not sure if that matters to anyone.
- My opinion is that all those content type headers are messy anyway and it would be nice (for me at least) to serve all the scripts via a single controller, adding the content type header automatically. Not a big deal but it removes a tiny bit of clutter from each script.
- If down the track, extensibility of the scripts, and modular design become a valid thing then having a controller will simplify the application. Especially if you want to read a config file or perform some logic that you wouldn't want polluting each script.
- the mod rewrite is just so the javascript requests to /sh/file.php get routed through xhr.php and I don't have to change javascript for the concept.

- I know testing, modularity, extensibility are roadmap items. These are of reasonable importance to me, so I'm just looking at some high level concepts on how this may or may not be achieved.