fabric: separate entry/class for scalable ep

The scalable endpoint is a different type of endpoint.

Scalable endpoints do not support any send/recv
operations. The application is required to create TX/RX
contexts off the scalable endpoint for communication.

Having a separate class and entrypoint for this type of
endpoint will help providers do a better job error-checking,
and simpler usage for apps.

Signed-off-by: Sayantan Sur <sayantan.sur@intel.com>
Merge pull request #340 from sayantansur/fi-class-sep

fabric.h: separate class for scalable endpoints
Updated nroff-generated man pages
fabric: create tx/rx ctx using scalable endpoints

This fixes some leftover issues in PR #340 that was
merged in c5a08e9.

The application creates a scalable endpoint, and must
use fid_sep in order to create the TX/RX contexts.

Also, include a separate fi_scalable_ep_bind() that
only documents binding an address vector to a scalable
endpoint.

Signed-off-by: Sayantan Sur <sayantan.sur@intel.com>
Merge pull request #346 from sayantansur/fi-sep-fixes

fabric: create tx/rx ctx using scalable endpoints
Updated nroff-generated man pages
Merge branch 'master' of ssh://github.com/ofiwg/libfabric