Switched from filewatcher to gaze

tl;dr - Replaces the filewatcher module with gaze because filewatcher wasn't working for me

Instant seemed like [exactly what I was looking for](https://twitter.com/jeremymorrell/status/450011320255909888) and I eagerly downloaded and tried it. The first change to my CSS file immediately showed up in my browser, and I clapped for joy! But then subsequent changes didn't have any effect. No!

Updating the file watcher to `gaze` which I'd used in the past and has a lot of community support seemed to fix my issues. I understand this might be a little contentious because `filewatcher` is one of your modules as well. However:

- `gaze` is becoming something of a standard
- is [constantly maintained with many contributors](https://github.com/shama/gaze) across many OSes and used in grunt and gulp
- and has an API that, at least for this project, is basically a one-to-one map to `filewatcher`