Update documentation with a working scala example of OpenID integration for play 2.2.x

 - Main change related to use of scala future (change to .map instead of .extend)
 - Add example of accessing information - email, name, image
 - Bit more realistic example of end to end processing of the messages with example
   of where to persist user data, flash for basic error messaging
 - Move code example to scala code
 - Remove deprecated AsyncResult