Update for the new code hinting API

Addresses issue #56 by updating the EWF extension to use the new [code hinting API](https://github.com/adobe/brackets/wiki/New-Code-Hinting-API-Proposal). 

Note that for this pull request only simple, unformatted hints are used so as to narrowly address #56. A subsequent pull request (#58) makes use of the jQuery formatting capabilities (enabled by adobe/brackets#2427) of the new code hint API to also format the font hints using the associated font family.