[ofw] Which API to use for IB project

[Sean Hefty]

>after playing around with libibverbs for a day and a half, I'm going
>to give uDAPL a try. The dapl specification is far superior to any
>documentation I found for libibverbs or winverbs, and all else being
>equal the portability and implementation effort determine the winner

There is no documentation for the winverbs API.  The code is still under initial
testing, so documentation will come a later.  The current users of winverbs are
libraries themselves (libibverbs, librdmacm, network direct, and DAPL), as
opposed to applications.

There are man pages for libibverbs/librdmacm available through the Linux
downloads that should apply for windows as well.  The verbs interface was
initially based on the Infiniband verbs as defined in the IBA specification -
mainly chapter 11.  So that would be usable as documentation as well.  Sample
apps exist for both libraries - their examples and the perftests.

DAPL definitely has more documentation and is the most portable option.  I don't
know how many applications use the DAPL interface beyond Intel's MPI.

- Sean