use CSRF/SecurityHeaders, update to Jquery 1.11.1, upgrade to latest pla...

...y/scala

Hi.
This patch mainly adds the CSRF & SecurityHeaders filters into Securesocial.

In order to get SecurityHeaders to work properly, I had to upgrade jQuery, and add a line to the application.conf to allow it to do inline-styles.
from my rudimentary testing, CSRF works.
I've also tested it when you don't have CSRF enabled in your app, and that seems to work as well.