[ofiwg] libfabric stable branch for 1.4

[Hefty, Sean]

We can queue this up for discussion at the next ofiwg.

Intel has a need to provide a critical, performance related fix.  (I.e. create a 1.4.2 release.)  Given the API changes driving release 1.5, I propose that we continue to maintain a 1.4 stable branch longer term.  This will ensure that distros that choose to support 1.4 have a forward path for obtaining bug fixes, since they hold upgrade library versions stable.

For a 1.4.2 release, we would need to identify if there are other fixes that can be pulled in, and what schedule will work.  I don't anticipate a significant amount of changes relative to 1.4.1, so a mid to late May release would be fine.

- Sean