Pass jslint

Thanks for the useful and interesting extension. I've made some changes that make the code pass JSLint (with the standard Brackets settings) and meet the [Brackets coding conventions](https://github.com/adobe/brackets/wiki/Brackets-Coding-Conventions).

Changes are:

1. Opening brackets of functions are placed at the end of the line, instead of on a new line
2. Variables are defined with `var` only once
3. Functions are defined before they're used
4. Doesn't use `this`. How it was used is a strict-mode violation
5. Doesn't use 'continue'. To do this, I use `forEach()` instead of `for` loops, which we can return early from