Update strategy.js

Facebook auth requests should use api v2.0 (as 'unversioned' 1.0 will be phased out)
https://developers.facebook.com/docs/apps/upgrading
Updated Facebook URLs to include API version (2.0).  Removed all
references to the 'username' field which is no longer returned.  Updated
tests to reflect app scoped IDs.
Merge remote-tracking branch 'mattdeluco/master'

Facebook APIv2.0
Merge remote-tracking branch 'preatorian/patch-1'

Facebook APIv2.0
bump version
Merge pull request #1 from stuartf/facebookApi2

Facebook api2