back like it was before I think I don't need that anymore with https://github.com/fotonauts/doolittle/commit/e5977c57d70df3a8e3c53192528ec1e99e65e96c
when cancelling an invitation, we don't receive a cancel, but we don't receive a post_id neither

Conflicts:
	src/FBDialog.m
Merge branch 'used_by_doolittle' of github.com:fotonauts/facebook-ios-sdk into used_by_doolittle