[TIDOC-1898] JavaScript version of "docgen -f jsduck"

**Install prerequisites.**  From the apidoc folder, run `npm install .`

**Sanity check.**  Run `node docgen.js -f jsduck`.  Should produce `../dist/titanium.js`

**Test.**
Merge in locally https://github.com/appcelerator/doctools/pull/62
Run `bash deploy.sh -o alloy -o modules`.
Open `dist/titanium/3.0/index.html`.
Inspect the API docs.  Make sure everything renders correctly, check platforms for API members, make sure the filters still work, etc.

Known issues.  API linking is broken for a few of the APIs as seen in the "Cannot find API" warnings.