Google Identity Toolkit + Google App Engine (Java)

Maven skeleton project built
Dependencies added
GitkitClient example code added (package com.google.identitytoolkit)
Properties with client id and service account mail added to WEB-INF (see SignInServlet)
p12 file in WEB-INF
Added browser API key and URL:s to widget.htm
Ignoring JAVASCRIPT_ESCAPED_POST_BODY

Install

Add your p12 key to 'src/main/webapp/WEB-INF/serviceaccountkey.data'
Create a properties file at 'src/main/webapp/WEB-INF/gitapp.properties' and add 'googleClientId' and 'serviceAccountEmail' properties
Run 'mvn appengine:devserver'