[app] Use more dot-notation syntax, as per @kylef’s request.
[app] Remove notification center registration.

Tip of the 'ol hat to @kylef for spotting this one.
[app] Cave in to people showing off their > 80 column displays.

:P

Now setting it to 100, because that's fine for GitHub reviewing
and for two vertical screens of code next to each other.
[app] Log commands by default in `DEBUG`.
[app] Small cleanups.
[app] Explicitly use `/bin/sh` to interpret env script.