New LFDS benchmarks

[hernanponcedeleon]

The benchmarks are already written in C so we probably only need to write some client code.

Stack: https://github.com/skeeto/lstack Queue: https://github.com/skeeto/scratch/blob/master/misc/queue.c

[ThomasHaas]

The stack requires a double-width CAS, which we don't support (yet). The queue might be doable, but it has a lot of bit vector reasoning.

[hernanponcedeleon]

Closing resource issues. They will remain available even if closed.