Removed some dependencies that were failing to build

I don't understand what was the purpose of these libs:

-   `pathwatcher` wasn't even used anywhere and was causing installation errors described in #2.
    I replaced the `pathwatcher.write` call with node.js `fs.writeFileSync`.
-   `fuzzaldrin`: Filtering suggestions is not needed because Racer is responsible for this.
According to the tutorial, you need to do this to get proper fuzzy filtering based on what the user has previously typed, see: https://github.com/atom-community/autocomplete-plus/wiki/Tutorial:-Registering-and-creating-a-suggestion-provider

Can you point me to some documentation or code showing this has changed?