ngdoc integration

[robhrt7]

Make ngdoc https://github.com/angular/angular.js/wiki/Writing-AngularJS-Documentation integration, using same approach as with DSS plugin https://www.npmjs.com/package/sourcejs-contrib-dss.

[robhrt7]

@dmitryshimkin is currently working on JSDoc integration to SourceJS and extendable API that will allow to add NGDoc like fields.

Hope this plugin will going to make it's way to open source.