liaison support.

The change adds three layers:

1. liaison/liaison: The base liaison code.
2. liaison/delite: liaison's delite integration code.
3. liaison/polymer: liaison's Polymer integration code.

The build will also include sample HTML files using build artifacts (except loan.html, which depends on Dojo loader due to dojox/charting usage).

The build picks up latest code of liaison's master branch, but if having release is preferred I can do it. Any questions/requests please let me know.