Facebook iOS SDK 3.11.1

Summary:
    see https://developers.facebook.com/ios/change-log-3.x/

Upgrading:
    https://developers.facebook.com/docs/ios/upgrading/

Reviewed By: jacl

Test Plan: Release Testing.
Facebook iOS SDK 3.12

Summary:
    see https://developers.facebook.com/ios/change-log-3.x/

Upgrading:
    https://developers.facebook.com/docs/ios/upgrading/
Facebook iOS SDK 3.13

Summary:
    see https://developers.facebook.com/ios/change-log-3.x/

Upgrading:
    https://developers.facebook.com/docs/ios/upgrading/
Merge upstream FacebookSDK v3.13