Summary:
This diff adds Xcode support for osquery.
Part of this diff will be reverted in future after adding prebuilt library and platform deps support to buck.
To use it you need to build osquery in debug mode and then run buck with following flags:
--config osquery.xcode=true --config project.ide=xcode
Reviewed By: SAlexandru
Differential Revision: D13903315
fbshipit-source-id: 4d131964d7a61236f25d917dc060a2f3c3d782bc
