Revert "Revert "Remove libcorkscrew.""

This reverts commit 767d3d7051da069c2645da9f7cf2fa732e8f1add.
Revert "Revert "Remove the dead corkscrew header files too.""

This reverts commit a80edb5e3bc9d951a1428386d959499cd4e2b68b.