added hidden tags for esri.github.io

This fixes the issue with portalpy displaying on [esri.github.io](http://esri.github.io). Currently, the codebase shows as HTML and it does not appear when filtering by keyword or tag.

HTML
![screen shot 2014-05-21 at 4 42 36 pm](https://cloud.githubusercontent.com/assets/240542/3046416/ad79a3fa-e128-11e3-936b-ba259e4ff4f2.png)


No search
![screen shot 2014-05-21 at 4 43 23 pm](https://cloud.githubusercontent.com/assets/240542/3046417/bad43ec0-e128-11e3-80c0-4d8c567967f8.png)