Facebook iOS SDK 3.5 (see https://developers.facebook.com/ios/change-log-3.x/)

Summary:
    See what's new
     https://developers.facebook.com/ios/features/whats-new-ios-sdk-3.5/
    Or read the announcement at
     https://developers.facebook.com/blog/post/2013/04/18/next-evolution-of-facebook-platform-for-mobile/

Reviewed By: jacl

Test Plan: Release Testing.

@update-submodule: vendor/OCHamcrest
@update-submodule: vendor/OCMock
@update-submodule: vendor/OHHTTPStubs
Facebook iOS SDK 3.5.1

Summary:
    Bug fixes. See https://developers.facebook.com/ios/change-log-3.x/

Reviewed By: jacl

Test Plan: Release Testing.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	samples/HelloFacebookSample/HelloFacebookSample/HFViewController.m