Add support for onfoo properties

Wrap all onfoo properties so that the function is called with a wrapped event
object.
fix submodule path
Update README.md
fix attributions
Merge branch 'master' of github.com:polymer-project/ShadowDOM
update tools
fix submodule paths
Fix HTMLLegendElement for FF21

In FF21 legend uses the old XPCOM binding which has issues that changing
window.HTLMElement changes any sub class that has HTMLElement in its prototype
chain. We therefore need to ensure that we do not override HTMLElement before
overriding HTMLLegendElement.
Merge pull request #151 from arv/fix-ff-21-ordering-issue

Fix HTMLLegendElement for FF21
add CLA, license, and patent file
add AUTHORS file
Merge pull request #147 from arv/on-event-properties

Add support for onfoo properties
buildbot.git no longer required