Databinding updates.
Live example for auto-binding, plus a small fix for include_external
Merge branch 'master' of https://github.com/Polymer/docs into databinding-updates
Update sample to include doctype and <head>.
Jumped the gun on inline function expressions. Reverting.
Updated to address comments.
Merge pull request #431 from arthurevans/databinding-updates

Databinding updates